Radio network, relay node, core node, relay transmission method used in the same and program thereof

ABSTRACT

A radio network can select a route of minimum path loss among entire relay routes and can set the relay route satisfactorily resistive against interference. The radio network has a core node connected to a wired network, relay nodes each relaying at least one of a down-link data packet transmitted from the core node and an up-link data packet directed toward the core node, and a terminal station capable of transmission and reception of data packet with both of the core node and the relay node. The relay node has total path loss to be minimum at least one of between relay nodes includes in a relay route of the data packet and between the relay node and the core node.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates generally to a radio network, arelay node, a core node, a relay transmission method used in the sameand a program thereof. More particularly, the invention relates to arelay route setting method and a relay transmission method in a cellularsystem, in which a plurality of nodes are connected by a radio network.

[0003] 2. Description of the Related Art

[0004] A cell structure in the conventional cellular system isillustrated in FIG. 20. In FIG. 20, the reference numeral 401 denotes acell, 402 denotes a base station (node). As shown in FIG. 20, a servicearea is constructed by arranging a plurality of cells as shown in FIG.20.

[0005] Each node are connected by a wired backbone network 404 throughwire lines 403 for transmitting service signal, such as voice, data andso forth and various control signals. It should be noted that the nodeand the wired backbone network may be connected by hierarchicallyproviding line concentration station therebetween.

[0006] A terminal station 405 communicates with a node 402 forperforming transmission and reception of various signals to betransmitted by a wired backbone network 404 through wire lines 403. Inthe wired backbone network, not only the radio base station (node) butalso a server equipment performing management of position information ofthe terminal station 405, billing process and so forth is provided.

[0007] In order to adapt for increasing of subscribers of cellularsystem, such as cellular telephone, subscriber fixed wireless access andso forth, radius of each cell is reduced to reduce process load in eachnode. When the system is constructed with such micro cells, quite largenumber of nodes are arranged in order to certainly establish the servicearea.

[0008] On the other hand, when a high density data transmission methodof multi-value modulation or the like is applied for adapting to a highspeed data transmission, service area to be covered by one nodeinherently becomes narrow for certainly quality. Even in such case,quite large number of nodes have to be arranged for certainlyestablishing service area.

[0009] Furthermore, the conventional cellular system has been mainlydesigned in a quasi-microwave band and microwave band, due to tightnessof frequencies, it has been desired to establish the cellular systemusing submillimeter wave or millimeter wave. When frequency becomeshigher, diffraction effect of the radio wave is reduced to makestraightening characteristics significant, and it causes difficulty innon line-of-sight communication to inherently narrow area of service ineach node. Namely, even in such case, the service area has to becertainly established with micro cells to install quite large number ofnodes.

[0010] When system is established with large number of micro cells, itbecomes essential to establish wired network for connecting the nodegroup to the backbone network. However, for connection between quitelarge number of geographically concentrated nodes and the backbonenetwork, wire line networks have to be extended to every places toinherently increase cost of the overall system. Therefore, there is amethod to establish connection between nodes with wireless communicationfor relay transmission to expand service area.

[0011] Setting of the relaying dominates a capacity because capacity ofthe cellular system is restricted by interference, and tolerance tointerference depends upon the setting of the relaying. In route methodthat makes number of relay nodes minimum, so-called minimum hop routingmethod, throughput or system capacity cannot be always maximum as viewedoverall relaying route for lacking of reception power due to distancebetween relay nodes and obstacles.

[0012] For achieving improvement of throughput and large circuitcapacity of overall system, setting method of the relay route becomesimportant. However, heretofore, there is not relay route setting methodspecialized radio relay transmission type cellular system in aconfiguration where a core node arranged a large number of micro cells,is connected to the wired backbone network and solving a problem ofinterference between the cells which causes problem in the cellularsystem.

SUMMARY OF THE INVENTION

[0013] The present invention has been worked out in view of the problemset forth above. It is therefore an object of the present invention toprovide a radio network, a relay node, a core node, a relay transmissionmethod used in the same and a program thereof, which can select a routeof minimum path loss among entire relay routes and can set the relayroute satisfactorily resistive against interference.

[0014] According to the first aspect of the present invention, a radionetwork comprises:

[0015] a core node connected to a wired network;

[0016] relay nodes each relaying at least one of a down-link data packettransmitted from the core node and an up-link data packet directedtoward the core node;

[0017] a terminal station capable of transmission and reception of datapacket with both of the core node and the relay node,

[0018] the relay node having total transmission loss to be minimum atleast one of between relay nodes includes in a relay route of the datapacket and between the relay node and the core node is selected.

[0019] According to the second aspect of the present invention, a radionetwork comprises:

[0020] a core node connected to a wired network; relay nodes eachrelaying at least one of a down-link data packet transmitted from thecore node and an up-link data packet directed toward the core node;

[0021] a terminal station capable of transmission and reception of datapacket with both of the core node and the relay node,

[0022] the relay node relaying the up-link data packet to other one ofup-link relay node and the core node when the up-link data packetaddressed to own node is received and relaying a down-link data packetto at least one down-link relay node when the down-link data packetaddress to the own node is received.

[0023] According to the third aspect of the present invention, a radionetwork comprises:

[0024] a relay node which forgets all of update metrics corresponding tothe route setting packets received in the past and relays a ner routesetting packet taking the update metric corresponding to the currentlyreceived route setting packet as net metric, when a sender nodeidentification information contained in the received route settingpacket matches a current up-link receiver side relay node. According tothe fourth aspect of the present invention, a radio network comprises:

[0025] a core node connected to a wired network; relay nodes eachrelaying at least one of a down-link data packet transmitted from thecore node and an up-link data packet directed toward the core node;

[0026] a terminal station capable of transmission and reception of datapacket with both of the core node and the relay node, a radio frequencyband to be used in relaying to be performed between the core node andthe relay node and between the relay nodes and a radio frequency band tobe used in access transmission to be performed between the core node andthe terminal station and between the relay node and the terminalstation, are different, and the radio frequency band to be used inrelaying is higher than the radio frequency band to be used in theaccess transmission.

[0027] According to the fifth aspect of the present invention, a relaynode relaying at least one of a down-link data packet transmitted fromthe core node and an up-link data packet directed toward the core node,and capable of communication with a terminal station, comprises:

[0028] an antenna for access transmission; an antenna for relaying;

[0029] a radio system for access transmission; and

[0030] a radio system for relaying,

[0031] a radio frequency band to be used in relaying to be performedbetween the core node and a radio frequency band to be used in accesstransmission to be performed between the terminal station, aredifferent, and the radio frequency band to be used in relaying is higherthan the radio frequency band to be used in the access transmission.

[0032] According to the sixth aspect of the present invention, a relaynode relaying at least one of a down-link data packet transmitted fromthe core node and an up-link data packet directed toward the core node,and capable of communication with a terminal station,

[0033] selecting relay nodes for making a total path loss in a relayroute of the data packet minimum from own node to the core node.According to the seventh aspect of the present invention, a relay noderelaying at least one of a down-link data packet transmitted from thecore node and an up-link data packet directed toward the core node, andcapable of communication with a terminal station,

[0034] relaying the up-link data packet to other one of up-link relaynode and the core node when the up-link data packet addressed to ownnode is received and relaying a down-link data packet to at least onedown-link relay node when the down-link data packet address to the ownnode is received.

[0035] According to the eighth aspect of the present invention, a relaynode relaying at least one of a down-link data packet transmitted fromthe core node and an up-link data packet directed toward the core node,and capable of communication with a terminal station,

[0036] a radio frequency band to be used in relaying to be performedbetween the core node and the relay node and between the relay nodes anda radio frequency band to be used in access transmission to be performedbetween the core node and the terminal station and between the relaynode and the terminal station, are different, and the radio frequencyband to be used in relaying is higher than the radio frequency band tobe used in the access transmission.

[0037] According to the ninth aspect of the present invention, a corenode capable of transmission and reception of data packet with either arelay node perform radio relaying and a terminal station, and connectedto a wired network, comprises: an antenna for access transmission;

[0038] an antenna for relaying;

[0039] a radio system for access transmission;

[0040] a radio system for relaying; and

[0041] a signal distributor connected to a wired backbone network, aradio frequency band to be used in relaying to be performed between therelay node and a radio frequency band to be used in access transmissionto be performed between the terminal station, are different, and theradio frequency band to be used in relaying is higher than the radiofrequency band to be used in the access transmission.

[0042] According to the tenth aspect of the present invention, a corenode connected to a wired network, being relayed at least one of adown-link data packet transmitted from own node and an up-link datapacket directed toward own node, and capable of transmission andreception of data packet with a terminal station, transmits a routesetting packet including a metric indicative of an amount providingindicia for selecting a sender identification information, an up-linkreceiver side relay node information and a receiver side relay node, tothe relay node.

[0043] According to the eleventh aspect of the present invention, a corenode connected to a wired network, being relayed at least one of adown-link data packet transmitted from own node and an up-link datapacket directed toward own node, and capable of transmission andreception of data packet with a terminal station, a radio frequency bandto be used in relaying to be performed between the core node and a radiofrequency band to be used in access transmission to be performed betweenthe terminal station, are different, and the radio frequency band to beused in relaying is higher than the radio frequency band to be used inthe access transmission.

[0044] According to the twelfth aspect of the present invention, arelaying method for a radio network including a core node connected to awired network, relay nodes each relaying at least one of a down-linkdata packet transmitted from the core node and an up-link data packetdirected toward the core node, and a terminal station capable oftransmission and reception of data packet with both of the core node andthe relay node, comprises the step of: selecting the relay node havingtotal path loss to be minimum at least one of between relay nodesincludes in a relay route of the data packet and between the relay nodeand the core node.

[0045] According to the thirteenth aspect of the present invention, arelaying method for a radio network including a core node connected to awired network, relay nodes each relaying at least one of a down-linkdata packet transmitted from the core node and an up-link data packetdirected toward the core node, and a terminal station capable oftransmission and reception of data packet with both of the core node andthe relay node, comprises steps of:

[0046] relaying the up-link data packet to other one of up-link relaynode and the core node when the up-link data packet addressed to ownnode is received and relaying a down-link data packet to at least onedown-link relay node when the down-link data packet address to the ownnode is received.

[0047] According to the fourteenth aspect of the present invention, arelaying method comprises:

[0048] a relay node which forgets all of update metrics corresponding tothe route setting packets received in the past and relays a new routesetting packet taking the update metric corresponding to the currentlyreceived route setting packet as net metric, when a sender nodeidentification information contained in the received route settingpacket matches a current up-link receiver side relay node.

[0049] According to the fifteenth aspect of the present invention, arelaying method for a system including core node connected to a wirednetwork, relay nodes each relaying at least one of a down-link datapacket transmitted from the core node and an up-link data packetdirected toward the core node, and a terminal station capable oftransmission and reception of data packet with both of the core node andthe relay node,

[0050] a radio frequency band to be used in relaying to be performedbetween the core node and the relay node and between the relay nodes anda radio frequency band to be used in access transmission to be performedbetween the core node and the terminal station and between the relaynode and the terminal station, are different, and the radio frequencyband to be used in relaying is higher than the radio frequency band tobe used in the access transmission.

[0051] According to the sixteenth aspect of the present invention, arelaying method for a radio network including a core node connected to awired network, relay nodes each relaying at least one of a down-linkdata packet transmitted from the core node and an up-link data packetdirected toward the core node, and a terminal station capable oftransmission and reception of data packet with both of the core node andthe relay node, comprises:

[0052] step of detecting arrival of a route setting packet including asender node identification information, an up-link receiver side relaynode information and a metric indicative of an amount providing anindicia for selecting the receiver side relay node;

[0053] step of making judgment whether the up-link receiver side relaynode indicates own node or not upon detection of arrival of the routesetting packet;

[0054] step of recording a node indicated by the sender nodeidentification information contained in the route setting packet in arelay node list when judgment is made that the up-link receiver sideinformation indicates own node;

[0055] step of taking a measured path loss upon judgment that theup-link receiver side node relay node information does not indicativeown node, as path loss Ln (n is unique number of a sender node of theroute setting packet) between the node transmitting the route settingpacket and the own node;

[0056] step of reading the metric Mr.n contained in the route settingpacket;

[0057] step of calculating and storing an update metric from the pathloss Ln and the metric Mr.n;

[0058] step of comparing the update metric Mn with the update metriccorresponding to the route setting packet received in the past formaking judgment whether the update metric Mn is minimum;

[0059] step of setting the update metric Mn to a metric contained in themetric of the route setting packet and registering the node indicated bythe sender node identification information of the currently arrivedroute setting packet as the up-link receiver side relay node when theupdate metric Mn is judged as minimum; and

[0060] step of transmitting a route setting packet containing thetransmission metric M as the metric, sender node identificationinformation indicating identification information of own node and theup-link receiver side relay node information.

[0061] According to the seventeenth aspect of the present invention, arelaying method for a radio network including a core node connected to awired network, relay nodes each relaying at least one of a down-linkdata packet transmitted from the core node and an up-link data packetdirected toward the core node, and a terminal station capable oftransmission and reception of data packet with both of the core node andthe relay node, comprises:

[0062] step of detecting arrival of a route setting packet including asender node identification information, an up-link receiver side relaynode information and a metric indicative of an amount providing anindicia for selecting the receiver side relay node;

[0063] step of making judgment whether the up-link receiver side relaynode indicates own node or not upon detection of arrival of the routesetting packet;

[0064] step of recording a node indicated by the sender nodeidentification information contained in the route setting packet in arelay node list when judgment is made that the up-link receiver sideinformation indicates own node;

[0065] step of taking a measured path loss upon judgment that theup-link receiver side node relay node information does not indicativeown node, as path loss Ln (n is unique number of a sender node of theroute setting packet) between the node transmitting the route settingpacket and the own node;

[0066] step of reading the metric Mr.n contained in the route settingpacket;

[0067] step of calculating and storing an update metric from the pathloss Ln and the metric Mr.n;

[0068] step of making judgment whether the sender node identificationinformation contained in the currently received route setting packetmatches with the current up-link receiver side relay node information ornot;

[0069] step of forgetting all stored update metrics when the sender nodeidentification information contained in the currently received routesetting packet matches with the current up-link receiver side relay nodeinformation;

[0070] step of comparing the update metric corresponding to the routesetting packet received in the past and the currently obtained updatemetric Mn when the sender node identification information contained inthe currently received route setting packet does not match with thecurrent up-link receiver side relay node information;

[0071] step of setting the update metric Mn to a metric contained in themetric of the route setting packet and registering the node indicated bythe sender node identification information of the currently arrivedroute setting packet as the up-link receiver side relay node when all ofthe update metrics are forgotten or when the update metric Mn is judgedas minimum; and

[0072] step of transmitting a route setting packet containing thetransmission metric M as the metric, sender node identificationinformation indicating identification information of own node and theup-link receiver side relay node information.

[0073] According to the eighteenth aspect of the present invention, arelaying method for a radio network including a core node connected to awired network, relay nodes each relaying at least one of a down-linkdata packet transmitted from the core node and an up-link data packetdirected toward the core node, and a terminal station capable oftransmission and reception of data packet with both of the core node andthe relay node, comprises:

[0074] step of detecting arrival of a route setting packet including asender node identification information, an up-link receiver side relaynode information and a metric indicative of an amount providing anindicia for selecting the receiver side relay node;

[0075] step of making judgment whether the up-link receiver side relaynode indicates own node or not upon detection of arrival of the routesetting packet;

[0076] step of recording a node indicated by the sender nodeidentification information contained in the route setting packet in arelay node list when judgment is made that the up-link receiver sideinformation indicates own node;

[0077] step of taking a measured path loss upon judgment that theup-link receiver side node relay node information does not indicativeown node, as path loss Ln (n is unique number of a sender node of theroute setting packet) between the node transmitting the route settingpacket and the own node;

[0078] step of reading the metric Mr.n contained in the route settingpacket;

[0079] step of calculating and storing an update metric from the pathloss Ln and the metric Mr.n;

[0080] step of comparing the update metric Mn with the update metriccorresponding to the route setting packet received in the past fordetermining a sender node m (m is unique number of node) having minimummetric;

[0081] step of making judgment whether the sender node m is the same asthe current up-link receiver side relay node and n≠m;

[0082] step of setting the update metric Mn to a metric contained in themetric of the route setting packet and registering the node indicated bythe sender node m as the up-link receiver side relay node when thesender node m is not the same as the current up-link receiver side relaynode or n=m; and

[0083] step of transmitting a route setting packet containing thetransmission metric M as the metric, sender node identificationinformation indicating identification information of own node and theup-link receiver side relay node information.

[0084] According to the nineteenth aspect of the present invention, aprogram of a relaying method for a radio network including a core nodeconnected to a wired network, relay nodes each relaying at least one ofa down-link data packet transmitted from the core node and an up-linkdata packet directed toward the core node, and a terminal stationcapable of transmission and reception of data packet with both of thecore node and the relay node, the program being executed by a computerfor implements the step of:

[0085] selecting the relay node having total path loss to be minimum atleast one of between relay nodes includes in a relay route of the datapacket and between the relay node and the core node.

[0086] According to the twentieth aspect of the present inventionprogram of a relaying method for a radio network including a core nodeconnected to a wired network, relay nodes each relaying at least one ofa down-link data packet transmitted from the core node and an up-linkdata packet directed toward the core node, and a terminal stationcapable of transmission and reception of data packet with both of thecore node and the relay node, the program being executed by a computerfor implements the step of:

[0087] relaying the up-link data packet to other one of up-link relaynode and the core node when the up-link data packet addressed to ownnode is received and relaying a down-link data packet to at least onedown-link relay node when the down-link data packet address to the ownnode is received.

[0088] According to the twenty-first aspect of the present invention, aprogram of a relaying method for a radio network including a core nodeconnected to a wired network, relay nodes each relaying at least one ofa down-link data packet transmitted from the core node and an up-linkdata packet directed toward the core node, and a terminal stationcapable of transmission and reception of data packet with both of thecore node and the relay node, the program being executed by a computerfor implements the step of:

[0089] step of detecting arrival of a route setting packet including asender node identification information, an up-link receiver side relaynode information and a metric indicative of an amount providing anindicia for selecting the receiver side relay node;

[0090] step of making judgment whether the up-link receiver side relaynode indicates own node or not upon detection of arrival of the routesetting packet;

[0091] step of recording a node indicated by the sender nodeidentification information contained in the route setting packet in arelay node list when judgment is made that the up-link receiver sideinformation indicates own node;

[0092] step of taking a measured path loss upon judgment that theup-link receiver side node relay node information does not indicativeown node, as path loss Ln (n is unique number of a sender node of theroute setting packet) between the node transmitting the route settingpacket and the own node;

[0093] step of reading the metric Mr.n contained in the route settingpacket;

[0094] step of calculating and storing an update metric from the pathloss Ln and the metric Mr.n;

[0095] step of comparing the update metric Mn with the update metriccorresponding to the route setting packet received in the past formaking judgment whether the update metric Mn is minimum;

[0096] step of setting the update metric Mn to a metric contained in themetric of the route setting packet and registering the node indicated bythe sender node identification information of the currently arrivedroute setting packet as the up-link receiver side relay node when theupdate metric Mn is judged as minimum; and

[0097] step of transmitting a route setting packet containing thetransmission metric M as the metric, sender node identificationinformation indicating identification information of own node and theup-link receiver side relay node information.

[0098] According to the twenty-second aspect of the present invention, aprogram of a relaying method for a radio network including a core nodeconnected to a wired network, relay nodes each relaying at least one ofa down-link data packet transmitted from the core node and an up-linkdata packet directed toward the core node, and a terminal stationcapable of transmission and reception of data packet with both of thecore node and the relay node, the program being executed by a computerfor implements the step of:

[0099] step of detecting arrival of a route setting packet including asender node identification information, an up-link receiver side relaynode information and a metric indicative of an amount providing anindicia for selecting the receiver side relay node;

[0100] step of making judgment whether the up-link receiver side relaynode indicates own node or not upon detection of arrival of the routesetting packet;

[0101] step of recording a node indicated by the sender nodeidentification information contained in the route setting packet in arelay node list when judgment is made that the up-link receiver sideinformation indicates own node;

[0102] step of taking a measured path loss upon judgment that theup-link receiver side node relay node information does not indicativeown node, as path loss Ln (n is unique number of a sender node of theroute setting packet) between the node transmitting the route settingpacket and the own node;

[0103] step of reading the metric Mr.n contained in the route settingpacket;

[0104] step of calculating and storing an update metric from the pathloss Ln and the metric Mr.n;

[0105] step of making judgment whether the sender node identificationinformation contained in the currently received route setting packetmatches with the current up-link receiver side relay node information ornot;

[0106] step of forgetting all stored update metrics when the sender nodeidentification information contained in the currently received routesetting packet matches with the current up-link receiver side relay nodeinformation;

[0107] step of comparing the update metric corresponding to the routesetting packet received in the past and the currently obtained updatemetric Mn when the sender node identification information contained inthe currently received route setting packet does not match with thecurrent up-link receiver side relay node information;

[0108] step of setting the update metric Mn to a metric contained in themetric of the route setting packet and registering the node indicated bythe sender node identification information of the currently arrivedroute setting packet as the up-link receiver side relay node when all ofthe update metrics are forgotten or when the update metric Mn is judgedas minimum; and

[0109] step of transmitting a route setting packet containing thetransmission metric M as the metric, sender node identificationinformation indicating identification information of own node and theup-link receiver side relay node information.

[0110] According to the twenty-third aspect of the present invention, aprogram of a relaying method for a radio network including a core nodeconnected to a wired network, relay nodes each relaying at least one ofa down-link data packet transmitted from the core node and an up-linkdata packet directed toward the core node, and a terminal stationcapable of transmission and reception of data packet with both of thecore node and the relay node, the program being executed by a computerfor implements the step of:

[0111] step of detecting arrival of a route setting packet including asender node identification information, an up-link receiver side relaynode information and a metric indicative of an amount providing anindicia for selecting the receiver side relay node;

[0112] step of making judgment whether the up-link receiver side relaynode indicates own node or not upon detection of arrival of the routesetting packet;

[0113] step of recording a node indicated by the sender nodeidentification information contained in the route setting packet in arelay node list when judgment is made that the up-link receiver sideinformation indicates own node;

[0114] step of taking a measured path loss upon judgment that theup-link receiver side node relay node information does not indicativeown node, as path loss Ln (n is unique number of a sender node of theroute setting packet) between the node transmitting the route settingpacket and the own node;

[0115] step of reading the metric Mr.n contained in the route settingpacket;

[0116] step of calculating and storing an update metric from the pathloss Ln and the metric Mr.n;

[0117] step of comparing the update metric Mn with the update metriccorresponding to the route setting packet received in the past fordetermining a sender node m (m is unique number of node) having minimummetric;

[0118] step of making judgment whether the sender node m is the same asthe current up-link receiver side relay node and n≠m;

[0119] step of setting the update metric Mn to a metric contained in themetric of the route setting packet and registering the node indicated bythe sender node m as the up-link receiver side relay node when thesender node m is not the same as the current up-link receiver side relaynode or n=m; and

[0120] step of transmitting a route setting packet containing thetransmission metric M as the metric, sender node identificationinformation indicating identification information of own node and theup-link receiver side relay node information.

[0121] Namely, the radio network according to the present inventiondetermines the core node among node groups deployed in certain area,connects the core node with the backbone network, and connects the corenode with wireless. The nodes other than the core node relays up-linkdata to the core node or relays the down-link data transmitted from thecore node.

[0122] By this, upon connecting the node groups with the backbonenetwork, only the core node and the backbone network are connected bywire line to permit reduction of installation cost of the wire line.Also, since connection of the node groups is established by radio,service area can be easily expanded.

[0123] The core node broadcasts the relay route setting packet. Therelay node measures the pathpath loss between the node transmitted thepacket and the own node by reception of the relay route setting packet.At the same time, with making reference to the metric contained in thepacket, the receiver side relay station is selected so that the pathloss becomes minimum by a sum of the measured path loss and the metric.Here, the metric represents a total path loss from the core node to thenode transmitted the relay route setting packet.

[0124] Each base station autonomously perform the foregoing operation.Therefore, receiver side in relay to have the minimum path loss can beselected over the relay route and can establish the relay routeresistive against interference which can be a significant problem in thecellular system.

[0125] Also, by using the path loss as metric, stable relay route notdepending upon interference power which is variable depending upontraffic, can be certainly established. On the other hand, even when thefrequency band is different, difference of the path loss is consideredto be small, in general. Therefore, even when different frequency bandsare used in up- and down-links, appropriate relay route can be obtained.

BRIEF DESCRIPTION OF THE DRAWINGS

[0126] The present invention will be understood more fully from thedetailed description given hereinafter and from the accompanyingdrawings of the preferred embodiment of the present invention, which,however, should not be taken to be limitative to the invention, but arefor explanation and understanding only.

[0127] In the drawings:

[0128]FIG. 1 is a diagrammatic illustration of one embodiment of acellular system according to the present invention;

[0129]FIG. 2 is an illustration showing one example of a structure of aroute setting packet;

[0130]FIG. 3 is a flowchart showing one example of a relay route settingprocess to be executed in each relay node in one embodiment of thepresent invention;

[0131]FIG. 4 is a flowchart showing one example of the relay routesetting process to be executed in a core node in one embodiment of thepresent invention;

[0132]FIG. 5 is an illustration showing one example of a structure of anup-link data packet;

[0133]FIG. 6 is a flowchart showing one example of a transmissionprocess of data packet in up-link;

[0134]FIG. 7 is an illustration showing a relay node list;

[0135]FIG. 8 is an illustration showing a data structure of a down-linkdata packet;

[0136]FIG. 9 is a flowchart showing one example of a down-link relaytransmission process in one embodiment of the present invention;

[0137]FIG. 10 is a flowchart showing one example of a receivingoperation of a terminal station in one embodiment of the presentinvention;

[0138]FIG. 11 is an illustration showing one example of a relay route inthe case where one embodiment of the relay route setting methodaccording to the present invention is employed;

[0139]FIG. 12 is an illustration for comparing one embodiment of therelay route setting method according to the invention and a minimum hopnumber relay route setting method;

[0140]FIG. 13 is a flowchart showing one example of the relay routesetting process to be executed in each relay node in another embodimentof the present invention;

[0141]FIG. 14 is a block diagram showing a construction of the node tobe used in one and another embodiments of the present invention;

[0142]FIG. 15 is a block diagram showing a construction of the relaynode to be used in one and another embodiments of the present invention;

[0143]FIG. 16 is a block diagram showing a construction of the core nodeto be used in one and another embodiments of the present invention;

[0144]FIG. 17 is a flowchart showing an example of another process in apart of the relay route setting process in one and another embodimentsof the present invention;

[0145]FIG. 18 is a flowchart showing one example of the relay routesetting process to be executed in each relay node in a furtherembodiment of the present invention;

[0146]FIG. 19 is a flowchart showing an example of another process in apart of the relay route setting process in another embodiment of thepresent invention; and

[0147]FIG. 20 is an illustration diagrammatically showing theconventional cellular system.

DESCRIPTION OF THE PREFERRED EMBODIMENT

[0148] The present invention will be discussed hereinafter in detail interms of the preferred embodiment of the present invention withreference to the accompanying drawings. In the following description,numerous specific details are set forth in order to provide a thoroughunderstanding of the present invention. It will be obvious, however, tothose skilled in the art that the present invention may be practicedwithout these specific details. In other instance, well-known structureare not shown in detail in order to avoid unnecessary obscurity of thepresent invention.

[0149]FIG. 1 is a diagrammatic illustration showing one embodiment of acellular system according to the present invention. In FIG. 1, thereference numeral 107 denotes a terminal station, 108 denotes a cell. Acore node 103 and a wired backbone 101 are connected by wire circuit102. Relay nodes 104 to 106 are connected to the core node 103 by radiorelay.

[0150] Each of the relay nodes and the core node may be provided withdirectional antenna. In such case, the directional antenna may befixedly set directional, or, in the alternative, may be setdirectionality adaptively. By installing directional antenna,interference given to neighboring nodes and the terminal stations can besuppressed, which realize high system capacity in overall system.

[0151] Other relay nodes shown in FIG. 1 are also connected to the corenode 103 through radio relay circuit, similarly to the relay nodes 104to 106. Setting of relay route of the radio relay circuit is initiatedby a route setting packet broadcasted from the core node 103. Namely,the relay node receiving the route setting packet broadcasted by thecore node 103 newly broadcast a route setting packet to other nodes. Inresponse to those broadcasted route setting packet sent by the relaynode, other relay nodes also broadcast the route setting packet. Thisoperation is repeated. Detail of transmission of the route settingpacket will be discussed later.

[0152]FIG. 2 is an illustration showing one example of a structure ofthe route setting packet. In FIG. 2, the route setting packet isconsisted of fields for transmitting respective of a sender node ID(identification information) A02, an up-link receiver side relay node IDA03, a metric A04 and others A01. It should be noted that order ofarrangement of respective elements can be different from an exampleshown in FIG. 2.

[0153] The sender node ID A02 indicates an ID number of the nodetransmitted the route setting packet. The up-link receiver side relaynode ID A03 indicates ID number of an up-link receiver side relay nodeset by the node broadcasting the route setting packet. In other A01,control signal, such as pilot signal or the like, data signal such assystem information and so forth, necessary for demodulation of thepacket, are included. The metric A04 indicates the amount of informationfor each node to select an up-link receiver side relay node.

[0154]FIG. 3 is a flowchart showing one example of a relay route settingprocess executed in each relay node in one embodiment of the presentinvention, and FIG. 4 is a flowchart showing one example of the relayroute setting process to be executed in a core node in one embodiment ofthe present invention. Updating method of the metric A04 and up-linkreceiver side node selecting procedure and route setting process in thecode node 103 depending upon the metric amount will be discussed withreference to FIGS. 1 to 4.

[0155] At first, transmission of the route setting packet is initiallyperformed by the core node 103. The relay route setting packetbroadcasted from the core node 103 is received by unspecified relaynodes 104 to 106. Namely, transmission of the route setting packet isperformed by broadcasting. At this time, since no up-link receiver siderelay node of the core node 103, the content of the up-link receiverside node ID A03 may be any ID as arbitrarily set.

[0156] The metric contained in the route setting packet broadcasted fromthe code node 103 is set to zero. A broadcasting interval of the routesetting packet may be set for regularly broadcasting, or in thealternative for broadcasting at random interval or in response to acommand from a server (not shown) on the wired backbone network 101.

[0157] The relay nodes 104 to 106 check whether the route setting packetarrived or not (step S1 of FIG. 3). If the route setting packet has notarrived, the process is returned to step S1. For detection of arrival ofthe route setting packet in the relay nodes 104 to 106, carrier sense orthe like is used. When arrival of the route setting packet is detected,the relay nodes 104 to 106 makes reference to the up-link receiver siderelay node ID contained in the route setting packet for checking whetherthe up-link receiver side relay node ID matches with the own node ID ornot (step S8 of FIG. 3).

[0158] When the receiver side relay node ID matches with the own nodeID, the relay nodes 104 to 106 record the ID of the node broadcasted theroute setting packet, namely the sender node ID contained in the routesetting packet in the relay node list (step S9 of FIG. 3).

[0159] The relay node list is a table indicating the down-link receiverside node ID number and is constructed as shown in FIG. 7. The relaynode list is used as receiver side node list upon the down-link datapacket relaying which will be discussed later. Each receiver side relaynode ID contained in the relay node list can be forgotten (erased) afterelapse of a given period. For instance, when new relay node is added inthe cell, when existing node moved or when new building is constructedin the cell, re-establishment of the relay route becomes necessary. Inorder to adapt to re-established relay route, each receiver side relaynode ID contained in the relay node list may be intentionally forgottenafter expiration of the given period.

[0160] If judgment is made that the relay node ID does not match withthe own node ID, the relay nodes 104 to 106 takes a path loss asmeasured at the timing of judgment, as a path loss Ln (n is specificnumber of the sender node of the route setting packet) between the nodethat broadcasted the route setting packet and the own node (step S2 ofFIG. 3). Measurement of the path loss is generally performed uponreception of the packet irrespective of the content. For measurement ofthe path loss, reception power of the packet or the like may be used. Inorder to facilitate measurement of the path loss, transmission power ofthe route setting packet can be fixed. It should be noted that nrepresents a node number and the node number n is designated by thesender node ID contained in the route setting packet.

[0161] The relay nodes 104 to 106 read the metric Mr, n contained in thereceived route setting packet (step S3 of FIG. 3). Here, the metric Mr,n represents total of path loss in the set route. Here, the set routemeans a route from the sender node of the received route setting packetto the core node.

[0162] The relay nodes 104 to 106 set an update metric Mn from thetransmission loss Ln measured at step S2 and the metric Mr.n. Here, theupdate metric Mn is given as a sum of the path loss Ln and the metricMr.n. The relay nodes 104 to 106 store the update metric Mn calculatedthrough the foregoing process (step S4 of FIG. 3). It should be notedthat, among stored update metric, the update metric maintained for aperiod in excess of a given period can be forgotten (erased). Forinstance, when new relay node is added in the cell, when new building isconstructed in the cell, re-establishment of the relay route becomesnecessary. In order to adapted to this, stored update metrics may beintentionally forgotten after expiration of the given period.

[0163] On the other hand, stored metric is made most recent constantly.Namely, when the update metric for the node n as sender of the routesetting packet was stored in the past, the past metric is re-written bythe new update metric derived at step S4.

[0164] The relay nodes 104 to 106 compares the update metric Mn and theupdate metric corresponding to the route setting packet received in thepast. If the newly obtained update metric Mn is not minimum (step S5 ofFIG. 3), the process is returned to step S1 and route setting packet isnot transmitted.

[0165] When the currently obtained update metric Mn is minimum (step S5of FIG. 3), the relay nodes 104 to 106 set the metric to be contained inthe metric A04 to the update metric Mn, and the node indicated by thesender node ID of the currently arrived route setting packet isregistered as the up-link receiver side relay node (step S6 of FIG. 3).Thus, the up-link receiver side relay node is only one in each node.

[0166] The relay nodes 104 to 106 sets the metric M set as set forthabove as metric and transmit the route setting packet with including thenecessary information in respective of other items shown in FIG. 2 (stepS7 of FIG. 3).

[0167] Upon reception of the route setting packet, the relay nodes 104to 106 may return an acknowledgement signal for accuracy. Since theroute setting packet is the control packet directed to unspecified node,the relay nodes 104 to 106 may receive the reception response signalsfrom a plurality of nodes after transmission of the route settingpacket. When the relay nodes 104 to 106 does not receive returnedreception response signal at all, re-transmission of the route settingpacket is performed.

[0168] On the other hand, the relay route setting process to be executedin a core node is different from that disclosed for relay nodes.Initially, the core node 103 checks whether the route setting packetarrived or not (step S11 of FIG. 4). If the route setting packet has notarrived, the process is returned top step S11. Even in the core node103, carrier sense or the like is used for detection of arrival of theroute setting packet. When the core node 103 detects arrival of theroute setting packet, the up-link receiver side relay node ID containedin the route setting packet is made reference to check whether theup-link receiver side node ID matches with the own node ID (step S12 ofFIG. 4).

[0169] When the up-link receiver side node ID matches with the own nodeID, the core node 103 records the node indicated in the ID of the routesetting packet transmitted by the other node, namely the sender node IDcontained in the route setting packet, in the relay node list (step S13of FIG. 4). The relay node list has the same function as those containedin the relay nodes 104 to 106. Namely, the relay node list is a tableindicating number ID of the down-link receiver side relay node andrespective receiver side relay node contained in the relay node list canbe forgotten (erased) after expiration of a given period.

[0170] Next, relay transmission of the data packet will be discussed.FIG. 5 is an illustration showing one example of the structure of theup-link data packet. In FIG. 5, the up-link receiver side data packet isconsisted of fields respectively transmitting a receiver side relay nodeID B02, a sender side relay node ID B03, a source terminal ID B04, adata B05 and other B01.

[0171] In the sender side relay node ID B03, the ID of the relay nodethat transmitted the up-link data packet or is going to transmit theup-link data packet is set. When the terminal transmits new up-link datapacket, special information indicative of a condition of the new up-linkdata packet other than node ID is contained in the sender side relaynode ID, is transmitted.

[0172] In the field of other B01, control information, such as pilotsignal for decoding, identification signal identifying up anddown-links, ID number of the data packet and so forth is contained. Itshould be noted that the order of the structural elements shown in FIG.5 should not be necessarily specific but can be different in any order.

[0173]FIG. 6 is a flowchart showing one example of a transmissionprocess of data packet in up-link. Relay transmission method of the datapacket in up- and down-links in one embodiment of the present inventionwill be discussed with reference to FIGS. 5 and 6. At first, in oneembodiment of the present invention, one example of the relaytransmission method of the up-link to be executed in each base stationin one embodiment of the present invention will be discussed.

[0174] The up-link data packet is transmitted to the code node 103 viathe relay nodes 104 to 106. The relay nodes 104 to 106 detect arrival ofthe up-link data packet (step S21 of FIG. 6). Here, for detection of thedata packet, carrier sense or the like is used. Judgment whether thedata packet of interest is up-link one or down-link is performeddepending upon the control information contained in the up-link datapacket shown in FIG. 5.

[0175] When a plurality of nodes relay the data packet from the sameterminal, it is possible that data packets of the same content arereceived from a plurality of sender nodes by one node. In such case,demoudulating may be performed by selecting only up-link data packethaving the highest reception quality or by combining the receivedsignals by diversity reception technique.

[0176] If arrival of the up-link data packet is not detected, the relaynodes 104 to 106 execute setp S11 again. On the other hand, when arrivalof the up-link data packet is detected, the relay nodes 104 to 106checks whether the arrived up-link data packet is the data pack on relayor the data packet newly transmitted from a terminal 107 (step S22 ofFIG. 6).

[0177] Here, upon making judgment wether the packet is the data packeton relay, the node 104 to 106 check the sender side node ID B03contained in the up-link data packet. For instance, if the sender siderelay node ID B03 indicates the ID of the own node, it is judged thatthe packet is a new up-link data packet.

[0178] Here, upon making judgment wether the packet if the data packeton relay, the relay node 104 to 106 check the sender side node ID B03contained in the up-link data packet. For instance, if the sender siderelay node ID B03 is the ID of the own node, it is judged that thepacket is a new up-link data packet.

[0179] Here, upon making judgment of the data packet on relay (otherthan new up-link data packet), the relay node 104 to 106 check thereceiver side relay node ID B02 contained in the data packet. If thereceiver side relay node ID B02 checked is not the ID of the own node(step S23 of FIG. 6), the process returns to step S21.

[0180] If the receiver side relay node ID B02 checked is the own node ID(step S23 of FIG. 6), the relay node 104 to 106 record the sender siderelay node ID B03 in the relay node list (step S24 of FIG. 6). Oneexample of the relay node list is shown in FIG. 7.

[0181] The relay node list is used as the receiver side node list upondown-link data packet relaying as will be discussed later. Each receiverside relay node ID B02 contained in the relay node list can be forgottenafter expiration of the given period. In the node not receiving theup-link data packet from the relay node, the relay node list becomesempty.

[0182] After recording the sender side relay node ID B03, the relaynodes 104 to 106 relay the data packet to the up-link receiver siderelay node set in the relay route setting process set forth above (stepS25 of FIG. 6). After relaying, the process returns to step S21.

[0183] Upon transmission of the up-link data packet, transmission powerof the data packet can be controlled so that the data packet may bereceived in the relay node or the receiver side relay node with a givenreception power or a given reception quality.

[0184] On the other hand, when judgment is made that the arrived up-linkdata packet is not on relaying but is newly generated from the terminalstation 107 (step S22 of FIG. 6), the relay nodes 104 to 106 relay thedata packet toward the receiver side relay node (step S25 of FIG. 6). Itshould be noted that recoding operation to the relay node list upon theup-link data packet shown in FIG. 6 is also performed upon relay routesetting packet transmission set forth above. For the reason of reductionof the process load, recording operation may not be implemented uponup-link data packet transmission.

[0185] The relaying of the up-link data packet in the core node issubstantially the same as that in the relay node shown in FIG. 6 exceptfor step S25. In the core node, instead of relaying the up-link datapacket to the receiver side relay node, the up-link data packet istransmitted to the wired backbone network.

[0186]FIG. 8 is an illustration showing a data structure of thedown-link data packet. In FIG. 8, the data packet is consisted of fieldsrespectively transmitting a receiver side relay node IS C02, a senderside relay node ID C03, a destination terminal ID C04, a data C05 andother C01.

[0187] In the field for the sender side relay node ID C03, ID of thecore node 103 transmitting the down-link data packet or the relay nodes104 to 106 is set. When a plurality of receiver side relay nodes arepresent, a plurality of receiver side relay node ID C02 are alsoprovided. On the other hand, the receiver side node ID C02 can set onlythe individual node ID but also dedicated ID indicative of all nodesincluded in the relay node list. In the field for other C01, controlinformation, such as pilot signal for demoudulating, identificationsignal of up- and down-link and packet ID number and so forth can becontained. It should be noted that the order of the structural elementshown in FIG. 8 should not be specific but can be different.

[0188]FIG. 9 is a flowchart showing one example of a down-link relaytransmission process in one embodiment of the present invention.Discussion will be given for one example of the down-link data packetrelaying process in one embodiment of the present invention will bediscussed with reference to FIGS. 8 and 9. It should be noted that theprocess shown in FIG. 9 is implemented in each relay nodes 104 to 106.

[0189] The relay nodes 104 to 106 monitors arrival of the down-link datapacket. If no down-link data packet newly arrives (step S31 of FIG. 9),the process is returned to step S31. Detection of arrival of thedown-link data packet is implemented by carrier sense or the like.

[0190] When the down-link data packet newly arrives (step S31 of FIG.9), the receiver side relay node contained in the down-link data packetis read. If the receiver side node ID does not match with the own nodeID (step S32 of FIG. 9), the process returns to step S31 not to performrelaying of the reception data packet.

[0191] If the receiver side relay node ID matches with the own node ID(step S32 of FIG. 9), the relay nodes 104 to 106 make reference to therelay node list produced upon relaying of the up-link data packet orrelaying of the route setting packet to select part of all of nodescontained in the relay node list to set as the receiver side relay nodefor the data packet (step S33 of FIG. 9).

[0192] Upon setting all nodes, particular identification numberdedicated therefor is set as the sender ID C04. The relay nodes 104 to106 relays the data packet after setting of the receiver side relay node(step S34 of FIG. 9).

[0193] Upon transmission of the down-link data packet, transmissionpower of the data packet can be controlled so that the data packet maybe received in the relay node or the receiver side relay node with agiven reception power or a given reception quality.

[0194] Relaying of the down-link data packet in the core node can be thesame as the method in the relay node shown in FIG. 9.

[0195]FIG. 10 is a flowchart showing one example of a receivingoperation of a terminal station 107 in one embodiment of the presentinvention. One example of receiving operation of the terminal station 10in one embodiment of the present invention will be discussed withreference to FIG. 10.

[0196] The terminal station 107 detects arrival of the down-link datapacket by carrier sense or the like to return to step S41 if arrival ofthe data packet is not detected (step S41 of FIG. 10). When arrival ofthe data packet is detected (step S41 of FIG. 10), the destinationterminal ID contained in the down-link data packet shown in FIG. 8 isread out. If the desitination terminal ID does not match with the ownterminal ID-(step S42 of FIG. 10), the process returns to step S41.

[0197] If the destination terminal ID matches with the own terminal ID(step S42 of FIG. 10), the terminal station 107 performs receptionprocess of the data contained in the data packet (step S43 of FIG. 10).Then, process returns to step S41.

[0198]FIGS. 11 and 12 are illustrations showing one example of the relayroute set by relay route setting in one embodiment of the presentinvention. FIG. 11 is an illustration showing one example of a relayroute in the case where one embodiment of the relay route setting methodaccording to the present invention is employed. In FIG. 11, a large dot201 represents the core node, and small dots 202, 204, 205 and so onrepresent relay nodes, and 203 denotes relay routes. At the relay node202, no down-link receiver side relay node is present, which means thatthe relay node list becomes empty in the relay node.

[0199]FIG. 12 is an illustration for comparing one embodiment of therelay route setting method according to the invention and a minimum hoprouting method. In FIG. 12, 301 denotes a wired backbone network, 302,303 and 304 are cells covered by the core nodes, 309 and elliptic areasnot identified by reference numeral are nodes covered by nodes otherthan core node. The reference numerals 310, 311, 312 are wire linesconnecting the core nodes and the wired backbone network 301.

[0200] One example of the relay route obtained by the relay routesetting method by one embodiment of the present invention is shown asradio relay circuits 307, 305 and 306. On the other hand, forcomparison, minimum hop routihg, number relaying, with minimum number ofrelay nodes, provides the radio relay route shown by reference numeral308 for example.

[0201] By using the relay route setting method of one embodiment of thepresent invention, selecting the route to have the minimum path loss inthe overall relay route can be realized. Then, relay route strongagainst interference can be realize.

[0202] On the other hand, in case of the minimum hop route shown in FIG.12, number of relay stations becomes smaller in comparison with theroute setting method in one embodiment of the present invention.However, considering overall relay route, total path loss becomesgreater than that in one embodiment of the present invention. Therefore,reliability of the overall radio relay route becomes low. In therelaying method in one embodiment of the present invention, the radiorelaying route having high reliability can be certainly established,which renders higher throughput in comparison with minimum hop routemethod.

[0203] In the down-link, using a relationship between the sender siderelay node and the receiver side relay node formed upon up-link packetrelay, the node served as sender side relay node in up-link is selectedas the receiver side relay node.

[0204] By using the path loss as the metric, stable relay routeindependent of interference power which is variable depending uponamount of traffic, can be certainly established. On the other hand,since difference of path loss for different frequency bans is generallyconsidered to be small appropriate relay route can be established ifdifferent frequency bands are used in the up- and down-link.

[0205] Only core node is connected to the backbone network by wire, andconnection between other node group and the backbone network isautomatically established by radio, therefor installation cost of thewire line can be reduced. Also, since the node groups are connected byradio, service area can be easily expanded. Furthermore, each node isnot constrained by wire, re-arrangement of node location can be doneeasily.

[0206] When the terminal moves between the nodes belonging the same corenode, it becomes unnecessary to access the mobile control station or thelike in the wired backbone network, and thus high speed hand-overbecomes possible.

[0207] As can be clear from the example shown in FIG. 11, when theup-link data packet transmitted by the terminal is received by aplurality of nodes, the same up-link data packet is relayed through aplurality of relay routes. As can be appreciated from the example shownin FIG. 11, in relaying of the up-link data packet, the relay routes areinherently coupled together on the way of relaying at certain node,diversity effect can be obtained by selecting one having good qualityupon receiving the data packet or by combining the same up-link datapacket in the node where the relay routes are coupled.

[0208] In the cellular system premised in one embodiment of the presentinvention, a terminated node of the up-link and a start node of thedown-link of the relay node are both core node. Therefore, in comparisonwith route setting in an adhoc network or the like, memory amount andcomplexity of the route setting.

[0209]FIG. 13 is a flowchart showing one example of the relay routesetting process to be executed in each relay node in another embodimentof the present invention. Another embodiment of the present inventionhas similar construction as the one embodiment of the cellular system ofthe present invention shown in FIG. 1, and the structure of the routesetting packet to be used in the operation thereof is also similar tothe structure of one embodiment of the route setting packet according tothe present invention shown in FIG. 2. With reference to FIGS. 1, 2 and13, updating method of the metric A01 and receiver side relay nodeselection procedure based on the metric in another embodiment of thepresent invention will be discussed.

[0210] Transmission of the route setting packet is initially performedby the core node 103. The relay route setting packet transmitted fromthe core node 103 to the unspecified relay nodes 104 to 106.

[0211] The metric contained in the route setting packet transmitted bythe core node 103 is set to zero. Transmission transmission interval ofthe route setting packet is set to be constant, to be random or is setin response to the command from the server on the wired backbonenetwork.

[0212] At first, the relay nodes 104 to 106 checks whether the routesetting packet arrived or not (step S51 of FIG. 13). If the routesetting packet does not arrive, the process returns to step S51.

[0213] The relay nodes 104 to 106 uses carrier sense or the like fordetection of arrival of the route setting packet. When arrival of theroute setting packet is detected (step S51 of FIG. 13), the relay node104 to 106 makes reference to the up-link receiver side relay node IDincluded in the route setting packet to make judgment whether theup-link receiver side relay node ID matches with the own node ID or not(step S60 of FIG. 13).

[0214] When the receiver side relay node ID matches with the own nodeID, the relay nodes 104 to 106 record the ID within the route settingpacket which the node broadcasted, namely the sender node ID containedin the route setting packet in the relay node list (step S61 of FIG. 3).

[0215] The relay node list is a table indicating the down-link receiverside node index and is constructed as shown in FIG. 7. The relay nodelist is used as receiver side node list for the down-link data packetrelaying which was discussed befor, and will be discussed later too.Each receiver side relay node ID contained in the relay node list can beforgotten (erased) after elapse of a given period. For instance, whennew relay node is added in the cell, when existing node moved or whennew building is constructed in the cell, re-establishment of the relayroute becomes necessary. In order to adapt to re-established relayroute, each receiver side relay node ID contained in the relay node listmay be intentionally forgotten after expiration of the given period.

[0216] If judgment is made that the relay node ID does not match withthe own node ID, the relay nodes 104 to 106 takes a path loss asmeasured at the timing of judgment, as a path loss Ln (n is specificnumber of the sender node of the route setting packet) between the nodethat broadcasted the route setting packet and the own node (step S62 ofFIG. 3). Measurement of the path loss is generally performed uponreception of the packet irrespective of the content. For measurement ofthe path loss, reception power of the packet or the like may be used. Inorder to facilitate measurement of the path loss, transmission power ofthe route setting packet can be fixed. It should be noted that nrepresents a node number and-the node number n is designated by thesender node ID contained in the route setting packet.

[0217] The relay nodes 104 to 106 read the metric Mr, n contained in thereceived route setting packet (step S53 of FIG. 3). Here, the metric Mr,n represents total of path loss in the set route. Here, the set routemeans a route from the sender node of the received route setting packetto the core node.

[0218] The relay nodes 104 to 106 set an update metric Mn from thetransmission loss Ln measured at step S52 and the metric Mr.n. Here, theupdate metric Mn is given as a sum of the path loss Ln and the metricMr.n. The relay nodes 104 to 106 store the update metric Mn calculatedthrough the foregoing process (step S54 of FIG. 3).

[0219] After setting the update metric Mn, if the sender node IDcontained in the currently received route setting packet matches withthe current up-link receiver side node ID of own node (step S55 of FIG.13), the metric M to be contained in the field of the metric A04 withthe update metric Mn and the node indicated by the sender node ID of thecurrently arrived route setting packet is registered as the receiverside relay node (step S58 of FIG. 13) after forgetting all of the storedupdate metric (step S56 of FIG. 13), Thus, up-link receiver side node isonly at each node.

[0220] The relay nodes 104 to 106 sets the metric M set as set forthabove as metric and transmit the route setting packet with including thenecessary information in respective of other items shown in FIG. 2 (stepS59 of FIG. 13).

[0221] On the other hand, when the sender node ID contained in thecurrently received route setting packet does not match with the currentup-link receiver side relay node ID (step S55 of FIG. 13), the updatemetric corresponding to the route setting packet received in the past iscompared with the newly obtained update metric Mn (step S57 of FIG. 13).

[0222] If the update metric Mn is minimum, the metric M to be containedin the field of the metric A04 is set with the update metric Mn, and thenode indicated by the sender node ID of the currently arrived routesetting packet is registered as the up-link receiver side relay node(step S58 of FIG. 13). Thus, up-link receiver side node is only at eachnode.

[0223] The relay nodes 104 to 106 set the transmission metric M set asset forth above as metric to transmit the route setting packet withcontaining necessary information in each item shown in FIG. 2 (step S59of FIG. 13). It should be noted that if the update metric is minimum,the process returns to step S51.

[0224] By forgetting update metric stored in each node and the receiverside relay node ID contained in the relay node list, re-establishment ofthe relay route becomes possible in case that modification of the relayroute becomes necessary due to variation of path loss between the nodesand addition or deletion or the like of the relay node.

[0225] On the other hand, in the relay node, concerning the case wherethe route setting packet transmitted from the current up-link receiverside relay node is received, all of stored update metrics correspondingto the past received route setting packets are forgotten. Andtransferring new update metric calculated from the metric contained inthe route setting packet to the route setting packet as new metric isperformed to promote updating of the route setting. Thus, it becomespossible to adapt for variation of the path loss in the current relayroute.

[0226] In the cellular system premised in another embodiment of thepresent invention, since the relay node is stationary arranged asinfrastructure, in comparison with the adhoc network, in which themoving terminal also serves as relay station, more stable communicationcan be performed. On the other hand, in the present invention, sinceboth of the terminated node of the up-link and the start node of thedown-link on the relay route are core node. Therefore, in comparisonwith route setting in an adhoc network or the like, memory amount andcomplexity of the route setting method can be reduced.

[0227] By controlling the transmission power of the uplink data packetor the downlink data packet, the interfarence to the nodes and theterminal station can be reduced. As a result, the capacity of the wholesystem can be improved.

[0228] In the radio network in the present invention, the radiofrequency band to be used for relaying between the core node and therelay node and between the relay nodes and the radio frequency band tobe used for access transmission to be performed between the core nodeand the terminal station or between the relay node and the terminalstation, can be the same or different. In transmission betweensemi-stationary arranged core node and relay node relative highfrequency can be used, such as submillimeter wave, millimeter wave orthe like. Because there are relatively large margin in frequencyresource and it becomes possible to use radio wave having straighttransmission characteristrics. On the other hand, in transmissionbetween the moving terminal station and the core node or between therelay nodes, relatively low frequency band, such as microwave band, isused to permit large capacity relaying and to permit access transmissioncapable of non line-of-sight communication.

[0229] In the embodiment set forth above, it is premised that radio waveis used in relaying and access transmission, it is possible to useinfrared light, light or the like in place of the radio wave.

[0230]FIG. 14 is a block diagram showing a construction of the node tobe used in one and another embodiments of the present invention. In FIG.14, the shown nodes are provided with directional antennas 11 to 1n. Thedirectional antennas 11 to in are connected to an antenna controller 1through signal lines 21 to 2n to permit control of respectivedirectionality by the antenna controller 1. Through the signal lines 21to 2n, transmission of the transmission and reception signals andtransmission of the control signal instructing the antenna direction areperformed.

[0231] The antenna controller 1 is connected to a transceiver 2 via asignal line 30 for transmission of the data signal and the controlsignal therethrough. The antenna controller 1 performs selecting controlor combining control of the transmission and reception antenna. IN thetransceiver, demodulation of the received data signal, modulation of thetransmission signal and so forth are unitarily processed.

[0232] In the construction shown in FIG. 14, a plurality of antennas areselected and used for one transceiver 2. However, it is also possible toperform plurality of transmission simultaneously by using theindependent transceiver for each antenna.

[0233] As set forth above, by using the directional antennas 11 to 1n,it becomes possible to compensate significant distance attenuation whichcan be caused in using high frequency, such as millimeter wave and toobtain large gain.

[0234] Since the present invention is directed to a network adaptivelysetting routes on the basis of the metrics from peripheral nodes, largegain can be obtained with respect to the node selected as route and canreduce interference for the nodes located nearby but out of the route bydirecting the transmission direction of the directional antennas 11 toin toward the node selected as the route. On the other hand, concerningthe route setting packet, a non-directional antenna may be used forwidely broadcasting to adjacent nodes.

[0235]FIG. 15 is a block diagram showing a construction of the relaynode to be used in one and another embodiments of the present invention.In FIG. 15, a construction of the relay node 3 is shown in the casewhere different radio frequency bands are used for access transmissionand relaying. In this case, the relay node 3 is provided with antennafor access 32 and a antenna for relay 31, and radio system for access 33and radio for relay system 34.

[0236] The radio system for access 33 and the radio system for relay 34includes modulator and demodulator, encoding and decoding device and soforth. The radio system for access 33 and the radio system for relay 34can exchange signal therebetween. The radio system for relay 34 performsrelaying on the basis of the route set by any one of the one embodimentof the invention and another embodiment of the invention. It should benoted that, in the route setting portion 36, setting of the route by anyone of the one embodiment of the invention and another embodiment of theinvention is performed by a program stored in a storage medium 37.

[0237] At first, discussion will be given for a manner of transmissionof an up-link traffic directed from the terminal station to the wiredbackbone network. The up-link traffic from the terminal stationgenerated in the cell of the own node is received by the accesstransmission antenna 32, is processed by the accessing radio system 33and is input to the radio system for relay 34. The radio system forrelay 34 transmits the up-link traffic toward the up-link receiver siderelay node using the antenna controller 35 and the antenna for relay 31.

[0238] Next, discussion will be given for operation for relaying thepacket from the terminal station generated in the cell of other relaynode. Namely, in the following discussion, operation in the relay nodeincluded in the route to the core node in the relay node, in which theterminal station generated the packet belongs is indicated. When thepacket from the terminal station is to be relayed, at first, the up-linkdata packet is received by the antenna for relay 31. The received signalis input to the radio system for relay 34. Then, operation shown in FIG.6 is performed. When relaying of the packet is decided, the radio systemfor relay 34 transmits the up-link traffic toward the up-link receiverside relay node using the antenna controller 35 and the antenna forrelay 31.

[0239] Subsequently, discussion will be given for a manner oftransmission of the down-link traffic from the wired backbone network tothe terminal station. The down-link traffic is at first received by theantenna for relay 31 and is input to the radio system for relay 34through the antenna controller 35. The radio system for relay 34 inputsthe down-link traffic to the radio system for acess 33 when the receiveddown-link traffic is address to the terminal in the cell of own node,and otherwise, the down-link receiver side relay node is determined onthe basis of the destination of the downlink packet and transmits thepacket through the antenna controller 35 and the antenna for relay 31.The radio system for acess 33 is responsive to input of the down-linktraffic to transmit the same to the terminal station through the antennafor acess 32.

[0240]FIG. 16 is a block diagram showing a construction of the core nodeto be used in one and another embodiments of the present invention. InFIG. 16, there is shown a construction of the core node in the casewhere different radio frequency bands for access transmission andrelaying. The core node 4 has similar construction as the relay node 3but is differentiated from the relay node as connected to the wiredbackbone network. A signal distributor 46 in the core node 4 isconnected to the wired backbone network 40, the radio system for acess43 and the radio system for relay 44, respectively.

[0241] The radio system for relay 44 performing relaying based on theroute set by any one of the one embodiment of the invention and anotherembodiment of the invention by a route setting portion 48. It should benoted that, in the route setting portion 46, setting of the route by anyone of the one embodiment of the invention and another embodiment of theinvention is performed by a program stored in a storage medium 49.

[0242] At first, discussion will be given for a manner of transmissionof an up-link traffic directed from the terminal station to the wiredbackbone network 40. The up-link traffic from the terminal stationgenerated in the cell is received by the access antenna for access 42,is processed by the radio system for access 43 and is input to thesignal distributor 46. The signal distributor 46 transmits the up-linktraffic to the wired backbone network 40.

[0243] Next, discussion will be given for operation for relaying thepacket from the terminal station generated in the cell of other relaynode. Namely, in the following discussion, operation in the case wherethe packet from the relay node, in which the terminal transmitted thepacket belongs, reaches core node is indicated. When the packet from theterminal station is to be relayed, at first, the up-link data packet isreceived by the antenna for relay 41. The received signal is input tothe relaying radio system 44. When confirmation is made that thereceived packet is up-link packet, the packet is transmitted to thewired backbone network through the signal distributor 46.

[0244] Subsequently, discussion will be given for a manner oftransmission of the down-link traffic from the wired backbone network 40to the terminal station. The down-link traffic is at first input to thesignal distributor 46. The signal distributor 46 makes judgment of theinput down-link traffic. If the down-link traffic is addressed to theterminal station within the cell of the own node, the traffic is inputto the radio system for access 43, and otherwise, is input to the radiosystem for relay 44. When the down-link traffic is input to the radiosystem for access 43, the traffic is transmitted to the terminal stationthrough the antenna for access 42. Then the down-link traffic is inputto the radio system for relay 44, the traffic is transmitted to theother relay node throuth the antenna for relay 41.

[0245] In one embodiment of the present invention, upon updating of pathloss as metric, new metric is constantly derived by adding the measuredtransmission loss Ln between the node that transmitted the route settingpacket and the own node to the metric Mr,n contained in the routesetting packet. However, it is also possible to generate the updatemetric by multiplying the received metric and the measured path loss bya weighting coefficient having a value in a range of 0 to 1. Namely, asweighting coefficient α, new update metric is derived by (Mr,n)×α+Ln×(1−α). With taking the value of α as 0.5, it becomes equivalent tothe case where weighting is not provided and is effective for reducingtransmission power in the overall system. On the other hand, by settingthe value of a zero, instead of path loss from the core node, only pathloss between the immediately adjacent node is considered to be effectivefor lowering of the transmission power in each node. Thus, by performingweighting upon updating of the metric, characteristics of the route canbe varied flexibly.

[0246] On the other hand, while one embodiment of the present inventionhas been discussed using only path loss as metric, it is possible to usetwo kinds of metrics. Namely, by providing two metrics of the firstmetric and the second metric, when the first metrics for multiple routesare the same, judgment is made by comparing the second metric forrespective routes. For example, the first metric is set a total of hopcount and the second metric is set a total of the path loss. Then, hopcount as the first metric is the same and minimum, one route havingsmaller path loss as second metric is taken as up-link side route totransmit new route setting packet and to set the up-link receiverside-relay node.

[0247] By this, more detailed route setting becomes possible to permitselection of the route having small path loss with restricting increaseof delay to be caused by increasing of the hop count to restrictinterference.

[0248] As set forth above, by using two kinds of metrics,characteristics of the generated route can be defined in detail to makethe network close to those expected by a designer.

[0249] On the other hand, when two kinds of metrics are used, uponmaking judgment as the same metric, width is provided for the judgmentreference to make the metric falling within a defined range as the samemetric. Namely, metrics to be considered as comparable extent areconsidered as the same to relay on judgment of the second metric.Discussion will be given hereinafter in the case where the path loss isclassified into reference per 10 dB (0 to 10 dB, 10 to 20 dB, . . . )with taking total of path loss as first metric and total hop count assecond metric, for example.

[0250] Assuming that three routes, route A, route B and route Crespectively having first and second metrics, route A=(81 dB, 3 hops),route B=(85 dB, 2 hops) and route C=(103 dB, 2 hops), are present. Atthis time, at first, the first metrics are compared. In the shown case,while magnitudes of the path losses per se are different between theroute A and the route B, in view of the reference of 10 dB unit, bothfalls within a reference value range of 80 to 90 dB. Therefore, thefirst metrics in the route A and the route B can be regarded as same.The route C has greater magnitude of path loss than those of the routesA and B even in view of the reference range of 10 dB unit. Therefore,the route C is not selected. Concerning the routes A and B judged tohave the same metric, two metrics are compared. Since the route B hassmaller hop count, i.e. second metric, the route B is selected as theroute.

[0251] As set forth, when two metrics are used, by providing width inthe reference range upon making judgment of large and small of themetric, two metrics are appropriately used to permit generation ofappropriate route.

[0252] By combining a method for multiplying weighting coefficient tothe metric and a method using two kinds of metrics, the followingoperation can be considered for example. Among two kinds of metrics, thehop count is taken as first metric. On the other hand, as second metric,with taking the path loss set forth above is taken as reference. Uponupdating of metric, with taking weighting coefficient a for hop count asfirst metric to be α=0.5, and 0.5 is constantly added upon updating ofmetric (since hop count is constantly increased by one, 1×0.5=0.5 isused), and as weighting coefficient β for path loss as second metric tobe β=0, the measured path loss per se is used as the update metric.

[0253] Namely, in FIGS. 3 and 13 showing the relay route settingprocess, the metric Mr,n to be read at step S3 or step S53 represents atotal of the hop number from the core node as the first metric and thepath loss as second metric. Updating of metric at step S4 or S54 isperformed respectively for the first metric and the second metric toobtain the update metric Mn.

[0254] Comparing the first update metric obtained from this result andthe first update metric corresponding to the route setting packet fromother node received in the past, the metric M is newly set in the updatemetric Mn when the newly obtained first update metric is minimum or thesame as the minimum value of the first update metric corresponding tothe route setting packet from other node received in the past, and whenthe second update metric is smaller than the second metric correspondingto the route having the minimum value of the first update metric, andthe node indicated by the sender node ID of the currently received setpacket is registered as up-link receiver side relay node.

[0255] Namely, in FIGS. 3 and 13, upon judgment of minimum metric atstep S5 or step S7, two kinds of metrics are used as set forth above.FIG. 17 shows a flowchart showing the operation. Steps S71 to S73 shownin FIG. 17 are replacement of step S5 or S57 in FIG. 3 or FIG. 13. Forexample, it is assumed as combination of the first metric and the secondmetric, three routes, route A=(3 hops, 100 dB), route B (3 hops, 91 dB)and route C (4 hops, 85 dB) are present. At first, the route C havinglarge hop count as the first metric is eliminated. Subsequently, bycomparing the second metrics, the route B is selected.

[0256]FIG. 18 is a flowchart showing one example of the relay routesetting process to be executed in each relay node in a furtherembodiment of the present invention. The further embodiment of thepresent invention has similar construction as one embodiment of thecellular system shown in FIG. 1 according to the present invention. Astructure of the route setting packet used in the operation of thefurther embodiment of the present invention is similar to the structureof the route setting packet in one embodiment of the present inventionshown in FIG. 2. Updating method of the metric A04 and receiver siderelay node selection procedure in the amount of the metric in thefurther embodiment of the present invention will be discussed withreference to FIGS. 1, 2 and 18.

[0257] Transmission of the route setting packet is initially performedby the core node 103. The relay route setting packet transmitted fromthe core node 103 is relayed to unspecified relay nodes 104 to 106.

[0258] The metric contained in the route setting packet transmitted bythe core node 103 is set to zero. When a transmission interval of theroute setting packet can be constant, random or on-demand in response toa command from the server on the wired backbone network 101.

[0259] At first, the relay nodes 104 to 106 check whether the routesetting packet arrived or not (step S81 of FIG. 18). If the routesetting packet is not detected, the process returns to step S81.

[0260] For detection of arrival of the route setting packet in the relaynodes 104 to 106, carrier sense or the like is used. When arrival of theroute setting packet is detected (step S81 of FIG. 18), the relay nodes104 to 106 makes reference to the receiver side relay node ID containedin the route setting packet for checking whether the receiver side relaynode ID matches with the own node ID or not (step S89 of FIG. 18).

[0261] When the receiver side relay node ID matches with the own nodeID, the relay nodes 104 to 106 record the ID of the node broadcasted theroute setting packet, namely the sender node ID contained in the routesetting packet in the relay node list (step S90 of FIG. 18).

[0262] The relay node list is a table indicating the down-link receiverside node number and is constructed as shown in FIG. 7. The relay nodelist is used as receiver side node list upon the down-link data packetrelaying which was discussed befor. Each receiver side relay node IDcontained in the relay node list can be forgotten (erased) after elapseof a given period. For instance, when new relay node is added in thecell, when existing node moved or when new building is constructed inthe cell, re-establishment of the relay route becomes necessary. Inorder to adapt to re-established relay route, each receiver side relaynode ID contained in the relay node list may be intentionally forgottenafter expiration of the given period.

[0263] If judgment is made that the relay node ID does not match withthe own node ID, the relay nodes 104 to 106 takes a path loss asmeasured at the timing of judgment, as a path loss Ln (n is specificnumber of the sender node of the route setting packet) between the nodebroadcasted the route setting packet and the own node (step S82 of FIG.18). Measurement of the path loss is generally performed upon receptionof the packet irrespective of the content. For measurement of the pathloss, reception power of the packet or the like may be used. In order tofacilitate measurement of the path loss, transmission power of the routesetting packet can be fixed. It should be noted that n represents a nodenumber and the node number n is designated by the sender node IDcontained in the route setting packet, as shown in FIG. 2.

[0264] The relay nodes 104 to 106 read the metric Mr, n contained in thereceived route setting packet (step S83 of FIG. 18). Here, the updatemetric Mr,n is given as a sum of the path loss. The relay node 104 to106 designate the update metric Mn from the path loss Ln and the metricMr,n measured in step S82. Here, the update metric Mn is given by thesum of the trasmission loss Ln and the metric Mr,n. The relay nodes 104to 106 store the update metric Mn calculated through the foregoingprocess (step S84 of FIG. 18).

[0265] It should be noted that, among stored update metric, the updatemetric maintained for a period in excess of a given period can beforgotten (erased). On the other hand, the stored metric is always themost recent one. Namely, when the update metric corresponding to thenode n as the sender of the route setting packet was stored in the past,the old metric is re-written with the new update metric obtained at stepS84.

[0266] The relay nodes 104 to 106 compares the update metric Mn withupdate metric corresponding to all route setting packet received in thepast to determine the sender node m (m is number specific to the node)as the smallest metric (step S85 of FIG. 18). If the sender node m isthe same as current up-link receiver side relay node of own node andn≠m(step@ S86 of FIG. 18), process is returned to step S81 andtransmission of the route setting packet is not newly performed.

[0267] If the sender node m having the minimum metric is not the same asthe current up-link receiver side node or n=m (step S86 of FIG. 18), theupdate metric Mn is set in the metric M contained in the metric A04, andthe sender node m is registered as up-link receiver side relay node ofown node (step S87 of FIG. 18). Namely, the route setting packet istransmitted when the up-link receiver side relay node is changed or whenthe route setting packet is received from the same up-link receiver siderelay node even if up-link receiver side relay node is not changed.

[0268] The relay nodes 104 to 106 sets the metric M set as set forthabove as metric and transmit the route setting packet with including thenecessary information in respective of other items shown in FIG. 2 (stepS88 of FIG. 18).

[0269] Upon reception of the route setting packet, the relay nodes 104to 106 may return an achnowledgement signal for accuracy. Since theroute setting packet is the control packet directed to unspecified node,the relay nodes 104 to 106 may receive the achnowledgement signals froma plurality of nodes after transmission of the route setting packet.When the relay nodes 104 to 106 does not receive returnedacknowledgement signal at all, re-transmission of the route settingpacket may be performed.

[0270] In FIG. 18, two kinds of metrics may be used as set forth aboveupon detection of the node having the minimum metric at step S85. FIG.19 is a flowchart showing an example of another process in a part of therelay route setting process in another embodiment of the presentinvention, in which steps S91 and S92 shown in FIG. 19 can bereplacement of step S85 in FIG. 18. For example, in case of combinationsof the first and second metrics are route A=(3 hops, 100 dB), route B (3hops, 91 dB) and route C (4 hops, 85 dB) are present. At first, theroute C having large hop count as the first metric is eliminated.Subsequently, by comparing the second metrics, the route B is selected.

[0271] As set forth above, the present invention can select the routehaving the minimum path loss in the entire relay route and can set therelay route resistive against interference by selecting the relay nodesto have total path loss in at least one of the routes between the relaynodes and between the relay node and the core node, in the radio networkincluding the core node connected to the wired network, the relay noderelaying at least one of the down-link data packet transmitted from thecore node and the up-link data packet, and a terminal station capable oftransmission and reception of the data packet with the core node and therelay node.

[0272] On the other hand, the present invention uses two kinds ofmetrics upon performing route control and calculates update metric withweighting to permit more flexible route setting to facilitate generationof the route having characteristics expected by the network designer.

[0273] Although the present invention has been illustrated and describedwith respect to exemplary embodiment thereof, it should be understood bythose skilled in the art that the foregoing and various other changes,omission and additions may be made therein and thereto, withoutdeparting from the spirit and scope of the present invention. Therefore,the present invention should not be understood as limited to thespecific embodiment set out above but to include all possibleembodiments which can be embodied within a scope encompassed andequivalent thereof with respect to the feature set out in the appendedclaims.

What is claimed is:
 1. A radio network comprising: core node connectedto a wired network; relay nodes each relaying at least one of adown-link data packet initially transmitted from said core node and anup-link data packet directed toward said core node; a terminal stationcapable of transmission and reception of data packet with both of saidcore node and said relay node, said relay node having total path loss tobe minimum at least one of between relay nodes includes in a relay routeof said data packet and between said relay node and said core node isselected.
 2. A radio network comprising: core nodes connected to a wirednetwork; relay nodes each relaying at least one of a down-link datapacket initially transmitted from said core node and an up-link datapacket directed toward said core node; a terminal station capable oftransmission and reception of data packet with both of said core nodeand said relay node, said relay node relaying said up-link data packetto other one of up-link relay node and said core node when the up-linkdata packet addressed to own node is receibed and relaying a down-linkdata packet to at least one down-link relay node when the down-link datapacket address to the own node is received.
 3. A radio network as setforth in claim 2, wherein said core node transmits a route settingpacket including a sender node identification information, an up-linkreceiver side relay node and a metric indicative of an amount providingcriteria for selecting said up-link receiver side node, said relay nodesets a sum of a metric contained in said route setting packet and a pathloss between a node transmitted said route setting packet and a nodereceiving said route setting packet as an update metric, when thecurrently obtained update metric is smaller than any of update metriccorresponding to route setting packets received in the past, a new routesetting packet containing said currently obtained update metric as newmetric is relayed to other relay node, a sender node informationindicative of the currently obtained route setting packet is set in theup-link receiver side relay node of own node, and information of saidreceiver side relay node is set in an up-link receiver side nodeinformation contained in new route setting packet.
 4. A radio network asset forth in claim 2, wherein said core node transmits a route settingpacket including a sender node identification information, an up-linkreceiver side relay node and a metric indicative of an amount providingcriteria for selecting said receiver side node, said relay node uses aweighting coefficient having a value of zero to one upon updating ofsaid metric when said route setting packet is received, decides a newupcate metric calculated by adding the metric contained in said routesetting packet multiplied by said weighting coefficient and the metricto be newly added multiplied by said weighting coefficient and themetric to be newly added multiplied by a value calculated by sibtractingsaid weighting coefficient from one.
 5. A radio network as set forth inclaim 4, wherein the metric contained in said route setting packet to bereceived by said relay node contains a metric generated based on a pathloss and a metric generated based on hop count indicating number ofrelay nodes included in said relay route.
 6. A radio network as setforth in claim 5, wherein said relay node updates the first metric usinga first weighting coefficient and updates the second metric using asecond weighting coefficient among metric contained in the route settingpacket upon reception of said route setting packet, relays new routesetting packet to taking the first and second update metrics as newmetric corresponding to the currently received route setting packet whensaid first update metric is smaller than any of the first update metricsreceived in the past and when the first update metric is the same as theminimum value of the first update metric corresponding to the routesetting packet received in the past and all of the second update metriccorresponding to the route setting packet received in the past andhaving the minimum first update metric are greater than the secondupdate metric corresponding to the route setting packet currentlyreceived, the sender node information indicated by said route settingpacket is set as an up-link receiver side relay node, and the up-linkreceiver side relay node information set in the up-link receiver siderelay node information contained in the new route setting packet.
 7. Aradio network as set forth in claim 6, wherein said first metric isgenerated on the basis of the hop count and said second metric isgenerated on the basis of the path loss.
 8. A radio network as set forthin claim 6, wherein, upon making judgment of large and small of said twokinds of metrics, metrics falls within a predetermined range is judgedas the same metric.
 9. A radio network as set forth in claim 6, wherein,upon updating the metric, 0.5 is used as a first weighting coefficientand 0.5 is used as a second weighting coefficient.
 10. A radio networkas set forth in claim 6, wherein, upon updating said metric, 0 is usedas a second weighting coefficient.
 11. A radio network comprising: arelay node which forgets all of update metrics corresponding to theroute setting packets received in the past and relays a new routesetting packet taking the update metric corresponding to the currentlyreceived route setting packet as new metric, when a sender nodeidentification information contained in the received route settingpacket matches a current up-link receiver side relay node of own node.12. A radio network as set forth in claim 3, wherein, after updating themetric contained in the received route setting packet, the sender nodeof the minimum metric among update metrics stored in the past includingthe currently updated update metric is determined, and a new routesetting packet taking the update metric corresponding to the determinedsender node as new metric, is relayed to other relay node when thesender node does not match with at least the current up-link receiverside relay node of own node.
 13. A radio network as set forth in claim7, wherein, after updating the metric contained in the received routesetting packet, sender nodes having the first metric to be the minimummetric among update metrics stored, are selected and the sender nodehaving the second metric to be minimum metric among said update metricsfor the selected sender nodes is decided, and a new route setting packettaking the update metric corresponding to the determined sender node asnew metric, is relayed to other relay node when the sender node does notmatch with at least the current up-link receiver side relay node of ownnode.
 14. A radio network as set forth in claim 3, wherein said relaynode makes reference to the up-link receiver side relay node informationcontained in said route setting packet upon receiving the route settingpacket, and records information of the node transmitted said routesetting packet in a relay node list when the up-link receiver side nodeinformation indicates own node.
 15. A radio network as set forth inclaim 3, wherein said core node makes reference to the up-link receiverside relay node information contained in said route setting packet uponreceiving the route setting packet, and records information of the nodetransmitted said route setting packet in a relay node list when theup-link receiver side node information indicates own node.
 16. A radionetwork as set forth in claim 14, wherein information relating to updatemetrics corresponding to the route setting packets received in the pastare erased after expiration of a given period.
 17. A radio network asset forth in claim 14, wherein said core node sets said metric containedin said route setting packet to zero.
 18. A radio network as set forthin claim 14, wherein the path loss is predicted from a reception powerof the received route setting packet.
 19. A radio network as set forthin claim 14, wherein said relay node transmits the up-link data packetto said up-link receiver side relay node upon reception of the up-linkdata packet transmitted from one of said terminal station and otherrelay nodes.
 20. A radio network as set forth in claim 19, wherein eachrelay node stores the sender side relay information contained in theup-link date packet transmitted to the own node in the relay node list.21. A radio network as set forth in claim 14, wherein said relay noderelays a down-link data packet to at least a part of nodes contained insaid relay node list upon relaying the down-link data packet.
 22. Aradio network as set forth in claim 21, wherein the information of thenodes contained in said relay node list is erased after expiration ofthe predetermined period.
 23. A radio network as set forth in claim 21,wherein the down-link data packet contains the terminal stationinformation, said terminal station performs reception process of thedown-link data packet when the terminal station information identifiesthe own station as checking the terminal station information containedin the down-link data packet transmitted from the adjacent relay node.24. A radio network as set forth in claim 21, wherein said relay nodeselects up-link data packet having higher reception quality when thesame up-link data packet is received from a plurality of sender siderelay nodes, for relaying.
 25. A radio network as set forth in claim 21,wherein said core node selects up-link data packet having higherreception quality when the same up-link data packet is received from aplurality of sender side relay nodes, for relaying.
 26. A radio networkas set forth in claim 21, wherein either of said relay node or said corenode performs mazimal ratio combining reception upon receiving the sameup-link data packets from a plurality of the sender side relay nodes.27. A radio network as set forth in claim 3, wherein said route settingpacket is transmitted at a constant transmission power in all of therelay nodes and the core nodes.
 28. A radio network as set forth inclaim 3, wherein said up-link data packet is controlled the transmissionpower for constant reception power or constant reception quality in therelay node or reception side relay node.
 29. A radio network as setforth in claim 3, wherein said down-link data packet is controlled thetransmission power for constant reception power or constant receptionquality in the relay node or reception side relay node.
 30. A radionetwork as set forth in claim 1, wherein a radio frequency band to beused in relaying to be performed between said core node and said relaynode and between said relay nodes and a radio frequency band to be usedin access transmission to be performed between said core node and saidterminal station and between said relay node and said terminal station,are different, and the radio frequency band to be used in relaying ishigher than the radio frequency band to be used in said accesstransmission.
 31. A radio network as set forth in claim 1, wherein eachof said core node and said relay node has a plurality of directionalantennas, each of said plurality of directional antennas is variable oftransmitting direction, each node controls transmitting direction of thedirectional antennas toward either of said core node and said relay nodelocated adjacent to said node.
 32. A radio network as set forth in claim31, wherein either of said core node and said relay node uses anon-directional antenna upon transmission of said route setting packet,and uses said directional antenna upon relaying of the data packet. 33.A radio network comprising: cores node connected to a wired network;relay nodes each relaying at least one of a down-link data packettransmitted from said core node and an up-link data packet directedtoward said core node; a terminal station capable of transmission andreception of data packet with both of said core node and said relaynode, a radio frequency band to be used in relaying to be performedbetween said core node and said relay node and between said relay nodesand a radio frequency band to be used in access transmission to beperformed between said core node and said terminal station and betweensaid relay node and said terminal station, are different, and the radiofrequency band to be used in relaying is higher than the radio frequencyband to be used in said access transmission.
 34. A radio network as setforth in claim 33, wherein each of said core node and said relay nodehas a plurality of directional antennas, each of said plurality ofdirectional antenna is variable of transmitting direction, each nodecontrols transmitting direction of the directional antennas their owntoward either of said core node and said relay node located adjacent tosaid node.
 35. A radio network as set forth in claim 34, wherein eitherof said core node and said relay node uses a non-directional antennaupon transmission of said route setting packet, and uses saiddirectional antennas upon relaying of the data packet.
 36. A relay noderelaying at least one of a down-link data packet initially transmittedfrom said core node and an up-link data packet directed toward said corenode, and capable of communication with a terminal station, comprising:antennas for access transmission; antenna for relaying; radio system foraccess transmission; and radio system for relaying, a radio frequencyband to be used in relaying to communicate with said core node and aradio frequency band to be used in access transmission to communicatewith said terminal station, are different, and the radio frequency bandto be used in relaying is higher than the radio frequency band to beused in said access transmission.
 37. A relay node relaying at least oneof a down-link data packet initially transmitted from said core node andan up-link data packet directed toward said core node, and capable ofcommunication with a terminal station, selecting relay nodes for makinga total path loss in a relay route of said data packet minimum from ownnode to the core node
 38. A relay node relaying at least one of adown-link data packet initially transmitted from said core node and anup-link data packet directed toward said core node, and capable ofcommunication with a terminal station, relaying the up-link data packetto other one of up-link relay node and said core node when the up-linkdata packet addressed to own node is recived and relaying a down-linkdata packet to at least one down-link relay node when the down-link datapacket address to the own node is received.
 39. A relay node as setforth in claim 38, wherein a route setting packet including a sendernode identification information, an up-link receiver side relay node anda metric indicative of an amount providing criteria for selecting saidup-link receiver side node from said core node or other relay node, saidrelay node sets a sum of a metric contained in said route setting packetand a path loss between a node transmitted said route setting packet anda node receiving said route setting packet as an update metric, when thecurrently obtained update metric is smaller than any of update metriccorresponding to route setting packets received in the past, a new routesetting packet containing said currently obtained update metric as newmetric is relayed to other relay nodes, a sender node informationindicative of the currently obtained route setting packet is set in theup-link receiver side relay node of own node, and information of saidreceiver side relay node is set in an up-link receiver side nodeinformation contained in new route setting packet.
 40. A relay node asset forth in claim 38, wherein a route setting packet including a sendernode identification information, an up-link receiver side relay node anda metric indicative of an amount providing criteria for selecting saidreceiver side node from said core node or other relay node, said relaynode uses a weighting coefficient having a value of zero to one uponupdating of said metric when said route setting packet is received,decides a new update metric calculated by adding the metric contained insaid route setting packet multipkied by said weighting coefficient andthe metric to be newly added multiplied by a value calculated bysubtracting said weighting coefficient from one.
 41. A relay node as setforth in claim 40, wherein the metric contained in said route settingpacket to be received by own node contains a metric generated based on apath loss and a metric generated based on hop count indicating number ofrelay nodes included in said relay route.
 42. A relay node as set forthin claim 41, which updates the first metric using a first weightingcoefficient and updates the second metric using a second weightingcoefficient among metric contained in the route setting packet uponreception of said route setting packet, relays new route setting packetto taking the first and second update metrics as new metriccorresponding to the currently received route setting packet when saidfirst update metric is smaller than any of the first update metricsreceived in the past and when the first update metric is the same as theminimum value of the first update metric corresponding to the routesetting packet received in the past and all of the second update metriccorresponding to the route setting packet received in the past andhaving the minimum first update metric are greater than the secondupdate metric corresponding to the route setting packet currentlyreceived, the sender node information indicated by said route settingpacket is set as an up-link receiver side relay node, and the up-lonkreceiver side relay node information set in the up-link receiver siderelay node information contained in the new route setting packet.
 43. Arelay node as set forth in claim 42, wherein said first metric isgenerated on the basis of the hop count and said second metric isgenerated on the basis of the path loss.
 44. A relay node as set forthin claim 42, wherein, upon making judgment of large and small of saidtwo kinds of metrics, metrics falls within a predetermined range isjudged as the same metric.
 45. A relay node as set forth in claim 42,wherein, upon updating the metric, 0.5 is used as a first weightingcoefficient and 0.5 is used as a second weighting coefficient.
 46. Arelay node as set forth in claim 42, wherein, upon updating said metric,0 is used as a second weighting coefficient.
 47. A relay node as setforth in claim 39, which forgets all of update metrics corresponding tothe route setting packets received in the past and relays a new routesetting packet taking the update metric corresponding to the currentlyreceived route setting packet as net metric, when a sender nodeidentification information contained in the received route settingpacket matches a current up-link receiver side relay node of own node.48. A relay node as set forth in claim 39, wherein, after updating themetric contained in the received route setting packet, the sender nodeof the minimum metric among update metrics stored in the past includingthe currently updated update metric is determined, and a new routesetting packet taking the update metric corresponding to the determinedsender node as new metric, is relayed to other relay node when thesender node does not match with at least the current up-link receiverside relay node of own node.
 49. A relay node as set forth in claim 43,wherein, after updating the metric contained in the received routesetting packet, sender nodes having the first metric to be the minimummetric among update metrics stored, are selected, the sender node havingthe second metric to be minimum metric among said update metrics for theselected sender nodes is decided, and a new route setting packet takingthe update metric corresponding to the determined sender node as newmetric, is relayed to other relay node when the sender node does notmatch with at least the current up-link receiver side relay node of ownnode.
 50. A relay node as set forth in claim 39, wherein said relay nodemakes reference to the up-link receiver side relay node informationcontained in said route setting packet upon receiving the route settingpacket, and records information of the node transmitted said routesetting packet in a relay node list when the up-link receiver side nodeinformation indicates own node.
 51. A relay node as set forth in claim50, wherein information relating to update metrics corresponding to theroute setting packets received in the past are erased after expirationof a given period.
 52. A relay node as set forth in claim 50, whereinthe path loss is predicted from a reception power of the route settingpacket received by the relay node.
 53. A relay node as set forth inclaim 50, wherein said relay node transmits the up-link data packet tosaid up-link receiver side relay node upon reception of the up-link datapacket transmitted from one of said terminal station and other relaynode.
 54. A relay node as set forth in claim 53, wherein each relay nodestores the sender side relay information contained in the up-link datapacket transmitted to the own node in its relay node list.
 55. A relaynode as set forth in claim 50, wherein said relay node relays adown-link data packet to at least a part of nodes contained in saidrelay node list upon relaying the down-link data packet.
 56. A relaynode as set forth in claim 55, wherein the information of the nodescontained in said relay node list is erased after expiration of thepredetermined period.
 57. A relay node as set forth in claim 55, wherein the down-link data packet contains the terminal station information,said terminal station performs reception process of the down-link datapacket when the terminal station information identifies the own stationas checking the terminal station information contained in the down-linkdata packet transmitted from the adjacent relay node.
 58. A relay nodeas set forth in claim 56, wherein said relay node selects up-link datapacket having higher reception quality when the same up-link data packetis received from a plurality of sender side relay nodes, for relaying.59. A relay node as set forth in claim 55, which performs maximal ratiocombining reception upon receiving the same up-link data packets from aplurality of the sender side relay nodes.
 60. A relay node as set forthin claim 39, wherein said route setting packet is transmitted at aconstant transmission power in all of the relay nodes and the corenodes.
 61. A relay node as set forth in claim 39, wherein said up-linkdata packet is controlled the transmission power for constant receptionpower or constant reception quality in the relay node or reception siderelay node.
 62. A relay node as set forth in claim 39, where in saiddown-link data packet is controlled the transmission power for constantreception power or constant reception quality in the relay node orreception side relay node.
 63. A relay node as set forth in claim 37,wherein a radio frequency band to be used in relaying to be performedbetween said core node and said relay node and between said relay nodesand a radio frequency band to be used in access transmission to beperformed between said core node and said terminal station and betweensaid relay node and said terminal station, are different, and the radiofrequency band to be used in relaying is higher than the radio frequencyband to be used in said access transmission.
 64. A relay node as setforth in claim 37, wherein each of said core node and said relay nodehas a plurality of directional antenna, each of said plurality ofdirectional antenna is variable of transmitting direction, each nodecontrols transmitting direction of the directional antennas towardeither of said core node and said relay node located adjacent to saidnode.
 65. A relay node as set forth in claim 64, which uses anon-directional antenna upon transmission of said route setting packet,and uses said directional antenna upon relaying of the data packet. 66.A relay node relaying at least one of a down-link data packettransmitted from said core node and an up-link data packet directedtoward said core node, and capable of communication with a terminalstation,a radio frequency band to be used in relaying to be performedbetween said core node and said relay node and between said relay nodesand a radio frequency band to be used in access transmission to beperformed between said core node and said terminal station and betweensaid relay node and said terminal station, are different, and the radiofrequency band to be used in relaying is higher than the radio frequencyband to be used in said access transmission.
 67. A relay node as setforth in claim 66, wherein each of said core node and said relay nodehas a plurality of directional antenna, each of said plurality ofdirectional antenna is variable of transmitting direction, each nodecontrols transmitting direction of the directional antennas towardeither of said core node and said relay node located adjacent to saidnode.
 68. A relay node as set forth in claim 67, which uses anon-directional antenna upon transmission of said route setting packet,and uses said directional antennas upon relaying of the data packet. 69.A core node capable of transmission and reception of data packet witheither a relay node that perform radio relaying and a terminal station,and connected to a wired network, comprising: an antenna for accesstransmission; an antenna for relaying; a radio system for accesstransmission; a radio system for relaying; and a signal distributorconnected to a wired backbone network,a radio frequency band to be usedin relaying to communicate said relay node and a radio frequency band tobe used in access transmission to communicate with said terminalstation, are different, and the radio frequency band to be used inrelaying is higher than the radio frequency band to be used in saidaccess transmission.
 70. A core node connected to a wired network, beingrelayed at least one of a down-link data packet transmitted from ownnode and an up-link data packet directed toward own node, and capable oftransmission and reception of data packet with a terminal station, andtransmitting a route setting packet including a metric indicative of anamount providing criteria for selecting an up-link receiver side relaynode an up-link receiver side relay node information and a receiver siderelay node, to said relay node.
 71. A core node as set forth in claim70, wherein said metric contained in said route setting packet is set tozero.
 72. A core node as set forth in claim 70, wherein the metriccontained in said route setting packet to be received by own nodecontains a metric generated based on a path loss and a metric generatedbased on hop count indicating number of relay nodes included in saidrelay route.
 73. A radio network as set forth in claim 70, wherein theup-link receiver side relay node information contained in said routesetting packet is made reference to upon receiving the route settingpacket and records information of the node transmitted said routesetting packet in a relay node list when the up-link receiver side nodeinformation indicates own node.
 74. A core node as set forth in claim73, wherein the information of the nodes contained in said relay nodelist is erased after expiration of the predetermined period.
 75. A corenode as set forth in claim 70, which selects the up-link data packethaving higher reception quality when the same up-link data packet isreceived from a plurality of sender side relay nodes, for relaying. 76.A core node as set forth in claim 70, wherein either of said relay nodeor said core node performs maximal ratio combining reception uponreceiving the same up-link data packets from a plurality of the senderside relay nodes.
 77. A core node as set forth in claim 70, wherein saidroute setting packet is transmitted at a constant transmission power inall of the relay nodes and the core nodes.
 78. A core node as set forthin claim 70, wherein said down-link data packet is controlled thetransmission power for constant reception power or constant receptionquality in the relay node or reception side relay node.
 79. A core nodeas set forth in claim 70, wherein a radio frequency band to be used inrelaying to communicate with said relay node and a radio frequency bandto be used in access transmission to communicate with said terminalstation, are different, and the radio frequency band to be used inrelaying is higher than the radio frequency band to be used in saidaccess transmission.
 80. A core node as set forth in claim 70, which hasa plurality of directional antennas, each of said plurality ofdirectional antennas is variable of transmitting direction, and controlstransmitting direction of the directional antennas their own towardeither of said relay node located adjacent.
 81. A core node as set forthin claim 80, which uses a non-directional antennas upon transmission ofsaid route setting packet, and uses said directional antenna uponrelaying of the data packet.
 82. A core node connected to a wirednetwork, being relayed at least one of a down-link data packettransmitted from own node and an up-link data packet directed toward ownnode, and capable of transmission and reception of data packet with aterminal station, a radio frequency band to be used in relaying tocommunicate with said relay node and a radio frequency band to be usedin access transmission to communicate with said terminal station, aredifferent, and the radio frequency band to be used in relaying is higherthan the radio frequency band to be used in said access transmission.83. A core node as set forth in claim 82, which has a plurality ofdirectional antennas, each of said plurality of directional antennas isvariable of transmitting direction, and controls transmitting directionof the directional antennas toward either of said relay node locatedadjacent.
 84. A core node as set forth in claim 83, which uses anon-directional antenna upon transmission of said route setting packet,and uses said directional antennas upon relaying of the data packet. 85.A relaying method for a radio network including a core node connected toa wired network, relay nodes each relaying at least one of a down-linkdata packet transmitted from said core node and an up-link data packetdirected toward said core node, and a terminal station capable oftransmission and reception of data packet with both of said core nodeand said relay node, comprising the step of: selecting said relay nodehaving total transmission loss to be minimum at least one of betweenrelay nodes includes in a relay route of said data packet and betweensaid relay node and said core node.
 86. A relaying method for a radionetwork including a core node connected to a wired network, relay nodeseach relaying at least one of a down-link data packet transmitted fromsaid core node and an up-link data packet directed toward said corenode, and a terminal station capable of transmission and reception ofdata packet with both of said core node and said relay node, comprisingsteps of: relaying said up-link data packet to other one of up-linkrelay node and said core node when the up-link data packet addressed toown node is received and relaying a down-link data packet to at leastone down-link relay node when the down-link data packet address to theown node is received.
 87. A relaying method as set forth in claim 86,wherein said core node transmits a route setting packet including asender node identification information, an up-link receiver side relaynode and a metric indicative of an amount providing an indicia forselecting said receiver side node, said relay node sets a sum of ametric contained in said route setting packet and a transmission lossbetween a node transmitted said route setting packet and a nodereceiving said route setting packet as an update metric, when thecurrently obtained update metric is smaller than any of update metriccorresponding to route setting packets received in the past, a new routesetting packet containing said currently obtained update metric as newmetric is relayed to other relay node, a sender node informationindicative of the currently obtained route setting packet is set in theup-link receiver side relay node, and information of said receiver siderelay node is set in an up-link receiver side node information containedin new route setting packet.
 88. A relaying method as set forth in claim86, wherein said core node transmits a route setting packet including asender node identification information, an up-link receiver side relaynode and a metric indicative of an amount providing an indicia forselecting said receiver side node, said relay node uses a weightingcoefficient having a value of zero to one upon updating of said metricwhen said route setting packet is received, multiplies said weightingcoefficient with the metric contained in said route setting packet,multiplying the metric to be added by a value calculated by subtractingsaid weighting coefficient from one and adding products from bothmultiplication to setting a resultant value as update metric.
 89. Arelaying method as set forth in claim 88, wherein the metric containedin said route setting packet to be received by said relay node containsa metric generated based on a path loss and a metric generated based onhop number indicating number of relay nodes included in said relayroute.
 90. A relaying method as set forth in claim 89, wherein saidrelay node updates the first metric using a first weighting coefficientand updates the second metric using a second weighting coefficient amongmetric contained in the route setting packet upon reception of saidroute setting packet, relays new route setting packet to taking thefirst and second update metrics as new metric corresponding to thecurrently received route setting packet when said first update metric issmaller than any of the first update metrics received in the past andwhen the first update metric is the same as the minimum value of thefirst update metric corresponding to the route setting packet receivedin the past and all of the second update metric corresponding to theroute setting packet received in the past and having the minimum firstupdate metric are greater than the second update metric corresponding tothe route setting packet currently received, the sender node informationindicated by said route setting packet is set in the up-link receiverside relay node, and the receiver side relay node information thus setus set in the up-link receiver side relay node information contained inthe new route setting packet.
 91. A relaying method as set forth inclaim 90, wherein said first metric is generated on the basis of the hopnumber and said second metric is generated on the basis of the pathloss.
 92. A relaying method as set forth in claim 90, wherein, uponmaking judgment of large and small of said two kinds of metrics, metricsfalls within a predetermined range is judged as the same metric.
 93. Arelaying method as set forth in claim 90, wherein, upon updating themetric, 0.5 is used as a first weighting coefficient and 0.5 is used asa second weighting coefficient.
 94. A relaying method as set forth inclaim 90, wherein, upon updating said metric, 0 is used as a secondweighting coefficient.
 95. A relaying method comprising: a relay nodewhich forgets all of update metrics corresponding to the route settingpackets received in the past and relays a new route setting packettaking the update metric corresponding to the currently received routesetting packet as net metric, when a sender node identificationinformation contained in the received route setting packet matches acurrent up-link receiver side relay node.
 96. A relaying method as setforth in claim 87, wherein, after updating the metric contained in thereceived route setting packet, the sender node of the minimum metricamong update metrics stored in the past including the currently updatedupdate metric is determined, and a new route setting packet taking theupdate metric corresponding to the determined sender core as new metric,is relayed to other relay node when the sender node does not match withat least the current up-link receiver side relay node.
 97. A relayingmethod as set forth in claim 91, wherein, after updating the metriccontained in the received route setting packet, the sender node havingthe first metric to be the minimum metric among update metrics stored,is selected, the sender node having the second metric to be minimummetric among said update metrics for the selected sender node and a newroute setting packet taking the update metric corresponding to thedetermined sender core as new metric, is relayed to other relay nodewhen the sender node does not match with at least the current up-linkreceiver side relay node.
 98. A relaying method as set forth in claim87, wherein said relay node makes reference to the up-link receiver siderelay node information contained in said route setting packet uponreceiving the route setting packet for recording information of the nodetransmitted said route setting packet in a relay node list when theup-link receiver side node information indicates own node.
 99. Arelaying method as set forth in claim 87, wherein said core node makesreference to the up-link receiver side relay node information containedin said route setting packet upon receiving the route setting packet forrecording information of the node transmitted said route setting packetin a relay node list when the up-link receiver side node informationindicates own node.
 100. A relaying method as set forth in claim 98,wherein information relating to update metrics corresponding to theroute setting packets received in the past are erased after expirationof a given period.
 101. A relaying method as set forth in claim 98,wherein said core node sets said metric contained in said route settingpacket to zero.
 102. A relaying method as set forth in claim 98, whereinthe transmission loss is predicted from a reception power of thereceived route setting packet.
 103. A relaying method as set forth inclaim 98, wherein said relay node transmits the up-link data packet tosaid up-link receiver side relay node upon reception of the up-link datapacket transmitted from one of said terminal station and other relaynode.
 104. A relaying method as set forth in claim 103, wherein eachrelay node stores the receiver side relay information contained in theup-link packet transmitted to the own node.
 105. A relaying method asset forth in claim 98, wherein said relay node relays a down-link datapacket to at least a part of nodes contained in said relay node listupon relaying the down-link data packet.
 106. A relaying method as setforth in claim 105, wherein the information of the nodes contained insaid relay node list is erased after expiration of the predeterminedperiod.
 107. A relaying method as set forth in claim 105, wherein thedown-link data packet contains the terminal station information, saidterminal station performs reception process of the down-link data packetwhen the terminal station information identifies the own station aschecking the terminal station information contained in the down-linkdata packet transmitted from the adjacent relay node.
 108. A relayingmethod as set forth in claim 105, wherein said relay node selectsup-link data packet having higher reception quality when the sameup-link data packet is received from a plurality of sender side relaynodes, for relaying.
 109. A relaying method as set forth in claim 105,wherein said core node selects up-link data packet having higherreception quality when the same up-link data packet is received from aplurality of sender side relay nodes, for relaying.
 110. A relayingmethod as set forth in claim 105, wherein either of said relay node orsaid core node performs maximum ratio combined reception upon receivingthe same up-link data packets from a plurality of the sender side relaynodes.
 111. A relaying method as set forth in claim 87, wherein saidroute setting packet is transmitted at a constant transmission power inall of the relay nodes and the core nodes.
 112. A relaying method as setforth in claim 87, wherein said up-link data packet is controlled thetransmission power for constant reception power or constant receptionquality in the relay node or reception side relay node.
 113. A relayingmethod as set forth in claim 87, wherein said down-link data packet iscontrolled the transmission power for constant reception power orconstant reception quality in the relay node or reception side relaynode.
 114. A relaying method as set forth in claim 85, wherein a radiofrequency band to be used in relaying to be performed between said corenode and said relay node and between said relay nodes and a radiofrequency band to be used in access transmission to be performed betweensaid core node and said terminal station and between said relay node andsaid terminal station, are different, and the radio frequency band to beused in relaying is higher than the radio frequency band to be used insaid access transmission.
 115. A relaying method as set forth in claim851, wherein each of said core node and said relay node has a pluralityof directional antenna, each of said plurality of directional antenna isvariable of transmitting direction, each node controls transmittingdirection of the directional antenna their own toward either of saidcore node and said relay node located adjacent to said node.
 116. Arelaying method as set forth in claim 115, wherein either of said corenode and said relay node uses a non-directional antenna upontransmission of said route setting packet, and uses said directionalantenna upon relaying of the data packet.
 117. A relaying method for asystem including core node connected to a wired network, relay nodeseach relaying at least one of a down-link data packet transmitted fromsaid core node and an up-link data packet directed toward said corenode, and a terminal station capable of transmission and reception ofdata packet with both of said core node and said relay node, a radiofrequency band to be used in relaying to be performed between said corenode and said relay node and between said relay nodes and a radiofrequency band to be used in access transmission to be performed betweensaid core node and said terminal station and between said relay node andsaid terminal station, being different, and the radio frequency band tobe used in relaying is higher than the radio frequency band to be usedin said access transmission.
 118. A relaying method as set forth inclaim 117, wherein each of said core node and said relay node has aplurality of directional antenna, each of said plurality of directionalantenna is variable of transmitting direction, each node controlstransmitting direction of the directional antenna their own towardeither of said core node and said relay node located adjacent to saidnode.
 119. A relaying method as set forth in claim 118, wherein eitherof said core node and said relay node uses a non-directional antennaupon transmission of said route setting packet, and uses saiddirectional antenna upon relaying of the data packet.
 120. A relayingmethod for a radio network including core nodes connected to a wirednetwork, relay nodes each relaying at least one of a down-link datapacket initially transmitted from said core node and an up-link datapacket directed toward said core node, and a terminal station capable oftransmission and reception of data packet with both of said core nodeand said relay node, comprising: step of detecting arrival of a routesetting packet including a sender node identification information, anup-link receiver side relay node information and a metric indicative ofan amount providing criteria for selecting an up-link receiver siderelay node; step of making judgment whether said up-link receiver siderelay node indicates own node or not upon detection of arrival of saidroute setting packet; step of recording a node indicated by said sendernode identification information contained in said route setting packetin a relay node list when judgment is made that said up-link receiverside information indicates own node; step of taking a measured path lossupon judgment that said up-link receiver side node relay nodeinformation does not indicative own node, as path loss Ln (n is uniquenumber of a sender node of said route setting packet) between the nodetransmitting said route setting packet and the own node; step of readingthe metric Mr.n contained in said route setting packet; step ofcalculating and storing an update metric from said path loss Ln and saidmetric Mr.n; step of comparing said update metric Mn with the updatemetric corresponding to the route setting packet received in the pastfor making judgment whether the update metric Mn is minimum; step ofsetting said update metric Mn to a metric field contained in a new routesetting packet and registering the node indicated by said sender nodeidentification information of the currently arrived route setting packetas said up-link receiver side relay node of own node when said updatemetric Mn is judged as minimum; and step of transmitting the new routesetting packet containing said metric Mn as a new metric M, sender nodeidentification information indicating identification information of ownnode and said up-link receiver side relay node information.
 121. Arelaying method for a radio network including a core node connected to awired network, relay nodes each relaying at least one of a down-linkdata packet initially transmitted from said core node and an up-linkdata packet directed toward said core node, and a terminal stationcapable of transmission and reception of data packet with both of saidcore node and said relay node, comprising: step of detecting arrival ofa route setting packet including a sender node identificationinformation, an up-link receiver side relay node information and ametric indicative of an amount providing criteria for selecting theup-link receiver side relay node; step of making judgment whether saidup-link receiver side relay node indicates own node or not upondetection of arrival of said route setting packet; step of recording anode indicated by said sender node identification information containedin said route setting packet in a relay node list when judgment is madethat said up-link receiver side information indicates own node; step oftaking a measured path loss upon judgment that said up-link receiverside node relay node information does not indicative own node, as pathloss Ln (n is unique number of a sender node of said route settingpacket) between the node transmitting said route setting packet and theown node; step of reading the metric Mr.n contained in said routesetting packet; step of calculating and storing an update metric fromsaid path loss Ln and said metric Mr.n; step of making judgment whetherthe sender node identification information contained in the currentlyreceived route setting packet matches with the current up-link receiverside relay node of own node or not; step of forgetting all stored updatemetrics when the sender node identification information contained in thecurrently received route setting packet matches with the current up-linkreceiver side relay node of own node; step of comparing the updatemetric corresponding to the route setting packet received in the pastand the currently obtained update metric Mn when the sender nodeidentification information contained in the currently received routesetting packet does not match with the current up-link receiver siderelay node of own node; step of setting said update metric Mn to ametric contained in a new route setting packet and registering the nodeindicated by said sender node identification information of thecurrently arrived route setting packet as said up-link receiver siderelay node of own node when all of said update metrics are forgotten orwhen said update metric Mn is judged as minimum; and step oftransmitting the new route setting packet containing said metric Mn as anew metric M, sender node identification information indicatingidentification information of own node and said up-link receiver siderelay node information.
 122. A relaying method for a radio networkincluding a core node connected to a wired network, relay nodes eachrelaying at least one of a down-link data packet initially transmittedfrom said core node and an up-link data packet directed toward said corenode, and a terminal station capable of transmission and reception ofdata packet with both of said core node and said relay node, comprising:step of detecting arrival of a route setting packet including a sendernode identification information, an up-link receiver side relay nodeinformation and a metric indicative of an amount providing criteria forselecting an up-link receiver side relay node; step of making judgmentwhether said up-link receiver side relay node indicates own node or notupon detection of arrival of said route setting packet; step ofrecording a node indicated by said sender node identificationinformation contained in said route setting packet in a relay node listwhen judgment is made that said up-link receiver side informationindicates own node; step of taking a measured path loss upon judgmentthat said up-link receiver side node relay node information does notindicative own node, as path loss Ln (n is unique number of a sendernode of said route setting packet) between the node transmitting saidroute setting packet and the own node; step of reading the metric Mr.ncontained in said route setting packet; step of calculating and storingan update metric from said path loss Ln and said metric Mr.n; step ofcomparing said update metric Mn with the updates metric corresponding tothe routes setting packet received in the past for determining a sendernode m (m is unique number of node) having minimum metric; step ofmaking judgment whether said sender node m is the same as the currentup-link receiver side relay node of own node and n≠m; step of settingsaid update metric Mn to a metric field contained in a new route settingpacket and registering the node indicated by said sender node m as saidup-link receiver side relay node of own node when said sender node m isnot the same as the current up-link receiver side relay node of own nodeor n=m; and step of transmitting the new route setting packet containingsaid metric Mn as a new metric M, sender node identification informationindicating identification information of own node and said up-linkreceiver side relay node information of own node.
 123. A program of arelaying method for a radio network including core nodes connected to awired network, relay nodes each relaying at least one of a down-linkdata packet initially transmitted from said core node and an up-linkdata packet directed toward said core node, and a terminal stationcapable of transmission and reception of data packet with both of saidcore node and said relay node, said program being executed by a computerfor implementing the step of: selecting said relay node having totalpath loss to be minimum at least one of between relay nodes includes ina relay route of said data packet and between said relay node and saidcore node.
 124. A program of a relaying method for a radio networkincluding cores node connected to a wired network, relay nodes eachrelaying at least one of a down-link data packet initially transmittedfrom said core node and an up-link data packet directed toward said corenode, and a terminal station capable of transmission and reception ofdata packet with both of said core node and said relay node, saidprogram being executed by a computer for implementing the step of:relaying said up-link data packet to other one of up-link relay node andsaid core node when the up-link data packet addressed to own node andrelaying a down-link data packet to at least one down-link relay nodewhen the down-link data packet address to the own node is received. 125.A program of a relaying method for a radio network including a core nodeconnected to a wired network, relay nodes each relaying at least one ofa down-link data packet transmitted from said core node and an up-linkdata packet directed toward said core node, and a terminal stationcapable of transmission and reception of data packet with both of saidcore node and said relay node, said program being executed by a computerfor implementing the step of: step of detecting arrival of a routesetting packet including a sender node identification information, anup-link receiver side relay node information and a metric indicative ofan amount providing an indicia for selecting the receiver side relaynode; step of making judgment whether said up-link receiver side relaynode indicates own node or not upon detection of arrival of said routesetting packet; step of recording a node indicated by said sender nodeidentification information contained in said route setting packet in arelay node list when judgment is made that said up-link receiver sideinformation indicates own node; step of taking a measured path loss uponjudgment that said up-link receiver side node relay node informationdoes not indicative own node, as path loss Ln (n is unique number of asender node of said route setting packet) between the node transmittingsaid route setting packet and the own node; step of reading the metricMr.n contained in said route setting packet; step of calculating andstoring an update metric from said transmission loss Ln and said metricMr.n; step of comparing said update metric Mn with the update metriccorresponding to the route setting packet received in the past formaking judgment whether the update metric Mn is minimum; step of settingsaid update metric Mn to a metric contained in the metric of said routesetting packet and registering the node indicated by said sender nodeidentification information of the currently arrived route setting packetas said up-link receiver side relay node when said update metric Mn isjudged as minimum; and step of transmitting a route setting packetcontaining said transmission metric M as said metric, sender nodeidentification information indicating identification information of ownnode and said up-link receiver side relay node information.
 126. Aprogram of a relaying method for a radio network including a core nodeconnected to a wired network, relay nodes each relaying at least one ofa down-link data packet transmitted from said core node and an up-linkdata packet directed toward said core node, and a terminal stationcapable of transmission and reception of data packet with both of saidcore node and said relay node, said program being executed by a computerfor implementing the step of: step of detecting arrival of a routesetting packet including a sender node identification information, anup-link receiver side relay node information and a metric indicative ofan amount providing an indicia for selecting the receiver side relaynode; step of making judgment whether said up-link receiver side relaynode indicates own node or not upon detection of arrival of said routesetting packet; step of recording a node indicated by said sender nodeidentification information contained in said route setting packet in arelay node list when judgment is made that said up-link receiver sideinformation indicates own node; step of taking a path transmission lossupon judgment that said up-link receiver side node relay nodeinformation does not indicative own node, as path loss Ln (n is uniquenumber of a sender node of said route setting packet) between the nodetransmitting said route setting packet and the own node; step of readingthe metric Mr.n contained in said route setting packet; step ofcalculating and storing an update metric from said transmission loss Lnand said metric Mr.n; step of making judgment whether the sender nodeidentification information contained in the currently received routesetting packet matches with the current up-link receiver side relay nodeinformation or not; step of forgetting all stored update metrics whenthe sender node identification information contained in the currentlyreceived route setting packet matches with the current up-link receiverside relay node information; step of comparing the update metriccorresponding to the route setting packet received in the past and thecurrently obtained update metric Mn when the sender node identificationinformation contained in the currently received route setting packetdoes not match with the current up-link receiver side relay nodeinformation; step of setting said update metric Mn to a metric containedin the metric of said route setting packet and registering the nodeindicated by said sender node identification information of thecurrently arrived route setting packet as said up-link receiver siderelay node when all of said update metrics are forgotten or when saidupdate metric Mn is judged as minimum; and step of transmitting a routesetting packet containing said transmission metric M as said metric,sender node identification information indicating identificationinformation of own node and said up-link receiver side relay nodeinformation.
 127. A program of a relaying method for a radio networkincluding a core node connected to a wired network, relay nodes eachrelaying at least one of a down-link data packet transmitted from saidcore node and an up-link data packet directed toward said core node, anda terminal station capable of transmission and reception of data packetwith both of said core node and said relay node, said program beingexecuted by a computer for implementing the step of: step of detectingarrival of a route setting packet including a sender node identificationinformation, an up-link receiver side relay node information and ametric indicative of an amount providing an indicia for selecting thereceiver side relay node; step of making judgment whether said up-linkreceiver side relay node indicates own node or not upon detection ofarrival of said route setting packet; step of recording a node indicatedby said sender node identification information contained in said routesetting packet in a relay node list when judgment is made that saidup-link receiver side information indicates own node; step of taking ameasured path loss upon judgment that said up-link receiver side noderelay node information does not indicative own node, as path loss Ln (nis unique number of a sender node of said route setting packet) betweenthe node transmitting said route setting packet and the own node; stepof reading the metric Mr.n contained in said route setting packet; stepof calculating and storing an update metric from said transmission lossLn and said metric Mr.n; step of comparing said update metric Mn withthe update metric corresponding to the route setting packet received inthe past for determining a sender node m (m is unique number of node)having minimum metric; step of making judgment whether said sender nodem is the same as the current up-link receiver side relay node and n≠m;step of setting said update metric Mn to a metric contained in themetric of said route setting packet and registering the node indicatedby said sender node m as said up-link receiver side relay node when saidsender node m is not the same as the current up-link receiver side relaynode or n=m; and step of transmitting a route setting packet containingsaid transmission metric M as said metric, sender node identificationinformation indicating identification information of own node and saidup-link receiver side relay node information.